diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7b1eafc..023e046 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,7 +6,7 @@ if(POLICY CMP0167)
 endif()
 
 project(Triangles
-    VERSION 6.0.0
+    VERSION 6.1.7
     DESCRIPTION "Cryptographic Triangles Wallet"
     LANGUAGES C CXX
 )
@@ -84,10 +84,10 @@ option(BUILD_QT           "Build triangles-qt (Qt5 GUI wallet)"              ON)
 option(BUILD_DAEMON       "Build trianglesd (headless daemon)"               ON)
 option(BUILD_CLI          "Build triangles-cli (JSON-RPC client)"            ON)
 option(BUILD_TESTS        "Build test_triangles (Boost.Test unit tests)"     ON)
-option(USE_UPNP           "Enable UPnP support via miniupnpc"               ON)
+option(USE_UPNP           "Enable UPnP support via miniupnpc"               OFF)
 option(USE_IPV6           "Enable IPv6 support"                              ON)
 option(USE_QRCODE         "Enable QR code generation via libqrencode"        OFF)
-option(USE_DBUS           "Enable D-Bus notifications (Linux only)"          ON)
+option(USE_DBUS           "Enable D-Bus notifications (Linux only)"          OFF)
 option(USE_ZMQ            "Enable ZMQ publisher support"                     OFF)
 # Triangles is Tor-native.  Tor is REQUIRED — disabling it at build time is
 # not a supported configuration.  The 2026-06-23 DNS2 clearnet-fork incident
@@ -104,7 +104,7 @@ if(DEFINED USE_TOR_EMBEDDED AND NOT USE_TOR_EMBEDDED)
         "instead.")
 endif()
 option(USE_O3             "Use -O3 optimization instead of -O2"              OFF)
-option(ENABLE_PIE         "Build position-independent executables"           OFF)
+option(ENABLE_PIE         "Build position-independent executables"           ON)
 option(ENABLE_STATIC      "Prefer static linking (Linux release builds)"     OFF)
 
 # Embedded I2P (i2pd) — runs an I2P router in-process alongside Tor.
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 4e552d7..61e7604 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -907,46 +907,48 @@ void StartShutdown() {}
     # "$@" preservation. We use bash explicitly (not sh) for "$@" array
     # semantics — paths may contain spaces, so word-splitting on IFS
     # would corrupt them.
-    file(WRITE "${FUZZ_LINK_WRAPPER}"
-"#!/bin/bash
+    set(FUZZ_LINK_WRAPPER_CONTENT [=[#!/bin/bash
 # Auto-generated by CMake (BUILD_FUZZ block). Discovers triangles_common +
 # trianglesd .o files at link time and exec's the clang++ link line.
 #
 # Usage: link.sh clang++ [link-args...]
 # Final exec: clang++ <each .o> <each original link-arg>
 set -euo pipefail
-PROG=\"\$1\"
+PROG="$1"
 shift
-TRIANGLES_COMMON_DIR=\"${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles/triangles_common.dir\"
-TRIANGLESD_DIR=\"${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles/trianglesd_objects.dir\"
+TRIANGLES_COMMON_DIR="@CMAKE_CURRENT_BINARY_DIR@/CMakeFiles/triangles_common.dir"
+TRIANGLESD_DIR="@CMAKE_CURRENT_BINARY_DIR@/CMakeFiles/trianglesd_objects.dir"
 # Discover .o files into a bash array. Exclude script.cpp.o (we have our
 # own clang-instrumented copy in fuzz_objs/ that we want to keep separate
 # from the main build's copy).
 declare -a OBJS=()
-for f in \"\$TRIANGLES_COMMON_DIR\"/*.o \"\$TRIANGLES_COMMON_DIR\"/*/*.o; do
-    [ -f \"\$f\" ] || continue
-    case \"\$f\" in
+for f in "$TRIANGLES_COMMON_DIR"/*.o "$TRIANGLES_COMMON_DIR"/*/*.o; do
+    [ -f "$f" ] || continue
+    case "$f" in
         */script.cpp.o) continue ;;
     esac
-    OBJS+=(\"\$f\")
+    OBJS+=("$f")
 done
-if [ -d "\$TRIANGLESD_DIR" ]; then
-    for f in "\$TRIANGLESD_DIR"/*.o; do
-        [ -f "\$f" ] || continue
+if [ -d "$TRIANGLESD_DIR" ]; then
+    for f in "$TRIANGLESD_DIR"/*.o; do
+        [ -f "$f" ] || continue
         # init.cpp defines the daemon's main(); the fuzz harness has its own
         # (libFuzzer's). wallet.cpp, noui.cpp etc. are safe — they don't
         # define main and their external references (pwalletMain,
         # uiInterface, nDerivationMethodIndex) are satisfied by the stub
         # object file we add at the end of the link line.
-        case "\$f" in
+        case "$f" in
             */init.cpp.o) continue ;;
         esac
-        OBJS+=("\$f")
+        OBJS+=("$f")
     done
 fi
 # Final arg list: PROG, then all .o files, then all original link args.
-exec \"\$PROG\" \"\${OBJS[@]}\" \"\$@\"
-")
+exec "$PROG" "${OBJS[@]}" "$@"
+]=])
+    string(CONFIGURE "${FUZZ_LINK_WRAPPER_CONTENT}"
+           FUZZ_LINK_WRAPPER_CONTENT @ONLY)
+    file(WRITE "${FUZZ_LINK_WRAPPER}" "${FUZZ_LINK_WRAPPER_CONTENT}")
     file(CHMOD "${FUZZ_LINK_WRAPPER}" PERMISSIONS
         OWNER_READ OWNER_WRITE OWNER_EXECUTE
         GROUP_READ GROUP_EXECUTE
diff --git a/src/bignum.h b/src/bignum.h
index d46786f..f4a05c8 100644
--- a/src/bignum.h
+++ b/src/bignum.h
@@ -14,6 +14,8 @@
 #include <openssl/opensslv.h>
 
 #include <algorithm>
+#include <cctype>
+#include <limits>
 #include <stdexcept>
 #include <vector>
 
@@ -69,16 +71,10 @@ public:
             throw bignum_error("CBigNum::CBigNum() : BN_new() returned NULL");
     }
 
-    CBigNum(const CBigNum& b)
+    CBigNum(const CBigNum& b) : CBigNum()
     {
-        pbn = BN_new();
-        if (pbn == nullptr)
-            throw bignum_error("CBigNum::CBigNum(const CBigNum&) : BN_new() returned NULL");
         if (!BN_copy(pbn, b.pbn))
-        {
-            BN_clear_free(pbn);
             throw bignum_error("CBigNum::CBigNum(const CBigNum&) : BN_copy failed");
-        }
     }
 
     CBigNum& operator=(const CBigNum& b)
@@ -99,21 +95,20 @@ public:
     const BIGNUM* get() const { return pbn; }
 
     //CBigNum(char n) is not portable.  Use 'signed char' or 'unsigned char'.
-    CBigNum(signed char n)        { pbn = BN_new(); if (n >= 0) setulong(n); else setint64(n); }
-    CBigNum(short n)              { pbn = BN_new(); if (n >= 0) setulong(n); else setint64(n); }
-    CBigNum(int n)                { pbn = BN_new(); if (n >= 0) setulong(n); else setint64(n); }
-    CBigNum(long n)               { pbn = BN_new(); if (n >= 0) setulong(n); else setint64(n); }
-    CBigNum(long long n)          { pbn = BN_new(); setint64(n); }
-    CBigNum(unsigned char n)      { pbn = BN_new(); setulong(n); }
-    CBigNum(unsigned short n)     { pbn = BN_new(); setulong(n); }
-    CBigNum(unsigned int n)       { pbn = BN_new(); setulong(n); }
-    CBigNum(unsigned long n)      { pbn = BN_new(); setulong(n); }
-    CBigNum(unsigned long long n) { pbn = BN_new(); setuint64(n); }
-    explicit CBigNum(uint256 n)   { pbn = BN_new(); setuint256(n); }
+    CBigNum(signed char n)        : CBigNum() { if (n >= 0) setulong(n); else setint64(n); }
+    CBigNum(short n)              : CBigNum() { if (n >= 0) setulong(n); else setint64(n); }
+    CBigNum(int n)                : CBigNum() { if (n >= 0) setulong(n); else setint64(n); }
+    CBigNum(long n)               : CBigNum() { if (n >= 0) setulong(n); else setint64(n); }
+    CBigNum(long long n)          : CBigNum() { setint64(n); }
+    CBigNum(unsigned char n)      : CBigNum() { setulong(n); }
+    CBigNum(unsigned short n)     : CBigNum() { setulong(n); }
+    CBigNum(unsigned int n)       : CBigNum() { setulong(n); }
+    CBigNum(unsigned long n)      : CBigNum() { setulong(n); }
+    CBigNum(unsigned long long n) : CBigNum() { setuint64(n); }
+    explicit CBigNum(uint256 n)   : CBigNum() { setuint256(n); }
 
-    explicit CBigNum(const std::vector<unsigned char>& vch)
+    explicit CBigNum(const std::vector<unsigned char>& vch) : CBigNum()
     {
-        pbn = BN_new();
         setvch(vch);
     }
 
@@ -216,21 +211,23 @@ public:
         pch[1] = (nSize >> 16) & 0xff;
         pch[2] = (nSize >> 8) & 0xff;
         pch[3] = (nSize) & 0xff;
-        BN_mpi2bn(pch, p - pch, pbn);
+        if (BN_mpi2bn(pch, static_cast<int>(p - pch), pbn) == nullptr)
+            throw bignum_error("CBigNum::setint64() : BN_mpi2bn failed");
     }
 
-    uint64_t getuint64()
+    uint64_t getuint64() const
     {
-        unsigned int nSize = BN_bn2mpi(pbn, nullptr);
-        if (nSize < 4)
+        const int nSize = BN_bn2mpi(pbn, nullptr);
+        if (nSize <= 4)
             return 0;
-        std::vector<unsigned char> vch(nSize);
-        BN_bn2mpi(pbn, &vch[0]);
+        std::vector<unsigned char> vch(static_cast<size_t>(nSize));
+        if (BN_bn2mpi(pbn, vch.data()) != nSize)
+            throw bignum_error("CBigNum::getuint64() : BN_bn2mpi failed");
         if (vch.size() > 4)
             vch[4] &= 0x7f;
         uint64_t n = 0;
-        for (unsigned int i = 0, j = vch.size()-1; i < sizeof(n) && j >= 4; i++, j--)
-            ((unsigned char*)&n)[i] = vch[j];
+        for (size_t i = 0; i < sizeof(n) && i + 4 < vch.size(); ++i)
+            n |= static_cast<uint64_t>(vch[vch.size() - 1 - i]) << (8 * i);
         return n;
     }
 
@@ -258,7 +255,8 @@ public:
         pch[1] = (nSize >> 16) & 0xff;
         pch[2] = (nSize >> 8) & 0xff;
         pch[3] = (nSize) & 0xff;
-        BN_mpi2bn(pch, p - pch, pbn);
+        if (BN_mpi2bn(pch, static_cast<int>(p - pch), pbn) == nullptr)
+            throw bignum_error("CBigNum::setuint64() : BN_mpi2bn failed");
     }
 
     void setuint256(uint256 n)
@@ -286,29 +284,33 @@ public:
         pch[1] = (nSize >> 16) & 0xff;
         pch[2] = (nSize >> 8) & 0xff;
         pch[3] = (nSize >> 0) & 0xff;
-        BN_mpi2bn(pch, p - pch, pbn);
+        if (BN_mpi2bn(pch, static_cast<int>(p - pch), pbn) == nullptr)
+            throw bignum_error("CBigNum::setuint256() : BN_mpi2bn failed");
     }
 
     uint256 getuint256() const
     {
-        unsigned int nSize = BN_bn2mpi(pbn, nullptr);
-        if (nSize < 4)
+        const int mpiSize = BN_bn2mpi(pbn, nullptr);
+        if (mpiSize <= 4)
             return 0;
-        std::vector<unsigned char> vch(nSize);
-        BN_bn2mpi(pbn, &vch[0]);
-        if (vch.size() > 4)
-            vch[4] &= 0x7f;
+        std::vector<unsigned char> vch(static_cast<size_t>(mpiSize));
+        if (BN_bn2mpi(pbn, vch.data()) != mpiSize)
+            throw bignum_error("CBigNum::getuint256() : BN_bn2mpi failed");
+        vch[4] &= 0x7f;
         uint256 n = 0;
-        for (unsigned int i = 0, j = vch.size()-1; i < sizeof(n) && j >= 4; i++, j--)
-            ((unsigned char*)&n)[i] = vch[j];
+        for (size_t i = 0; i < sizeof(n) && i + 4 < vch.size(); ++i)
+            reinterpret_cast<unsigned char*>(&n)[i] = vch[vch.size() - 1 - i];
         return n;
     }
 
 
     void setvch(const std::vector<unsigned char>& vch)
     {
+        if (vch.size() > static_cast<size_t>(std::numeric_limits<int>::max() - 4))
+            throw bignum_error("CBigNum::setvch() : input is too large");
+
         std::vector<unsigned char> vch2(vch.size() + 4);
-        unsigned int nSize = vch.size();
+        const uint32_t nSize = static_cast<uint32_t>(vch.size());
         // BIGNUM's byte stream format expects 4 bytes of
         // big endian size data info at the front
         vch2[0] = (nSize >> 24) & 0xff;
@@ -316,20 +318,25 @@ public:
         vch2[2] = (nSize >> 8) & 0xff;
         vch2[3] = (nSize >> 0) & 0xff;
         // swap data to big endian
-        reverse_copy(vch.begin(), vch.end(), vch2.begin() + 4);
-        BN_mpi2bn(&vch2[0], vch2.size(), pbn);
+        for (size_t i = 0; i < vch.size(); ++i)
+            vch2.at(i + 4) = vch.at(vch.size() - 1 - i);
+        if (BN_mpi2bn(vch2.data(), static_cast<int>(vch2.size()), pbn) == nullptr)
+            throw bignum_error("CBigNum::setvch() : BN_mpi2bn failed");
     }
 
     std::vector<unsigned char> getvch() const
     {
-        unsigned int nSize = BN_bn2mpi(pbn, nullptr);
-        if (nSize <= 4)
+        const int mpiSize = BN_bn2mpi(pbn, nullptr);
+        if (mpiSize <= 4)
             return std::vector<unsigned char>();
-        std::vector<unsigned char> vch(nSize);
-        BN_bn2mpi(pbn, &vch[0]);
-        vch.erase(vch.begin(), vch.begin() + 4);
-        reverse(vch.begin(), vch.end());
-        return vch;
+        std::vector<unsigned char> mpi(static_cast<size_t>(mpiSize));
+        if (BN_bn2mpi(pbn, mpi.data()) != mpiSize)
+            throw bignum_error("CBigNum::getvch() : BN_bn2mpi failed");
+
+        std::vector<unsigned char> result(static_cast<size_t>(mpiSize - 4));
+        for (size_t i = 0; i < result.size(); ++i)
+            result.at(i) = mpi.at(mpi.size() - 1 - i);
+        return result;
     }
 
     CBigNum& SetCompact(unsigned int nCompact)
@@ -340,16 +347,20 @@ public:
         if (nSize >= 1) vch[4] = (nCompact >> 16) & 0xff;
         if (nSize >= 2) vch[5] = (nCompact >> 8) & 0xff;
         if (nSize >= 3) vch[6] = (nCompact >> 0) & 0xff;
-        BN_mpi2bn(&vch[0], vch.size(), pbn);
+        if (BN_mpi2bn(vch.data(), static_cast<int>(vch.size()), pbn) == nullptr)
+            throw bignum_error("CBigNum::SetCompact() : BN_mpi2bn failed");
         return *this;
     }
 
     unsigned int GetCompact() const
     {
-        unsigned int nSize = BN_bn2mpi(pbn, nullptr);
-        std::vector<unsigned char> vch(nSize);
-        nSize -= 4;
-        BN_bn2mpi(pbn, &vch[0]);
+        const int mpiSize = BN_bn2mpi(pbn, nullptr);
+        if (mpiSize <= 4)
+            return 0;
+        std::vector<unsigned char> vch(static_cast<size_t>(mpiSize));
+        if (BN_bn2mpi(pbn, vch.data()) != mpiSize)
+            throw bignum_error("CBigNum::GetCompact() : BN_bn2mpi failed");
+        const unsigned int nSize = static_cast<unsigned int>(mpiSize - 4);
         unsigned int nCompact = nSize << 24;
         if (nSize >= 1) nCompact |= (vch[4] << 16);
         if (nSize >= 2) nCompact |= (vch[5] << 8);
@@ -361,7 +372,7 @@ public:
     {
         // skip 0x
         const char* psz = str.c_str();
-        while (isspace(*psz))
+        while (isspace(static_cast<unsigned char>(*psz)))
             psz++;
         bool fNegative = false;
         if (*psz == '-')
@@ -369,15 +380,15 @@ public:
             fNegative = true;
             psz++;
         }
-        if (psz[0] == '0' && tolower(psz[1]) == 'x')
+        if (psz[0] == '0' && tolower(static_cast<unsigned char>(psz[1])) == 'x')
             psz += 2;
-        while (isspace(*psz))
+        while (isspace(static_cast<unsigned char>(*psz)))
             psz++;
 
         // hex string to bignum
         static constexpr signed char phexdigit[256] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,1,2,3,4,5,6,7,8,9,0,0,0,0,0,0, 0,0xa,0xb,0xc,0xd,0xe,0xf,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0xa,0xb,0xc,0xd,0xe,0xf,0,0,0,0,0,0,0,0,0 };
         *this = 0;
-        while (isxdigit(*psz))
+        while (isxdigit(static_cast<unsigned char>(*psz)))
         {
             *this <<= 4;
             int n = phexdigit[(unsigned char)*psz++];
@@ -389,6 +400,8 @@ public:
 
     std::string ToString(int nBase=10) const
     {
+        if (nBase < 2 || nBase > 16)
+            throw bignum_error("CBigNum::ToString() : base must be in [2, 16]");
         CAutoBN_CTX pctx;
         CBigNum bnBase = nBase;
         CBigNum bn0 = 0;
diff --git a/src/bootstrap.cpp b/src/bootstrap.cpp
index 48cf7af..96d058b 100644
--- a/src/bootstrap.cpp
+++ b/src/bootstrap.cpp
@@ -4,6 +4,7 @@
 #include "bootstrap.h"
 #include "utxosnapshot.h"
 #include "txdb.h"
+#include "checkpoints.h"
 
 #include <filesystem>
 #include <fstream>
@@ -22,6 +23,7 @@
 #include "key.h"
 #include "base58.h"
 #include "util.h"
+#include "json/nlohmann_json.hpp"
 
 extern const std::string strMessageMagic;
 
@@ -30,12 +32,14 @@ extern const std::string strMessageMagic;
 #include <cstdio>
 #include <cstring>
 #include <cstdlib>
+#include <cctype>
 
 #ifdef WIN32
 #include <winsock2.h>
 #include <ws2tcpip.h>
 #else
 #include <sys/socket.h>
+#include <sys/time.h>
 #include <netdb.h>
 #include <unistd.h>
 #endif
@@ -88,6 +92,20 @@ static SOCKET ConnectDirectTCP(const std::string& host, int port, std::string& s
         if (hSocket == INVALID_SOCKET)
             continue;
 
+        // A bootstrap endpoint must not be able to wedge daemon startup by
+        // accepting a connection and then never sending a response.
+#ifdef WIN32
+        DWORD timeoutMs = 30000;
+        setsockopt(hSocket, SOL_SOCKET, SO_RCVTIMEO,
+                   reinterpret_cast<const char*>(&timeoutMs), sizeof(timeoutMs));
+        setsockopt(hSocket, SOL_SOCKET, SO_SNDTIMEO,
+                   reinterpret_cast<const char*>(&timeoutMs), sizeof(timeoutMs));
+#else
+        struct timeval timeout = {30, 0};
+        setsockopt(hSocket, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout));
+        setsockopt(hSocket, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout));
+#endif
+
         if (connect(hSocket, rp->ai_addr, (int)rp->ai_addrlen) == 0)
             break; // success
 
@@ -154,8 +172,11 @@ struct HttpConn {
             strError = "Failed to create SSL context";
             return false;
         }
-        // Skip cert verification — we verify data integrity via checkpoint hashes
-        SSL_CTX_set_verify(ctx, SSL_VERIFY_NONE, nullptr);
+        if (SSL_CTX_set_default_verify_paths(ctx) != 1) {
+            strError = "Failed to load the system TLS trust store";
+            return false;
+        }
+        SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, nullptr);
 
         ssl = SSL_new(ctx);
         if (!ssl) {
@@ -163,7 +184,11 @@ struct HttpConn {
             return false;
         }
         SSL_set_fd(ssl, (int)sock);
-        SSL_set_tlsext_host_name(ssl, hostname.c_str()); // SNI
+        if (SSL_set_tlsext_host_name(ssl, hostname.c_str()) != 1 ||
+            SSL_set1_host(ssl, hostname.c_str()) != 1) {
+            strError = "Failed to configure TLS hostname verification for " + hostname;
+            return false;
+        }
 
         if (SSL_connect(ssl) != 1) {
             unsigned long err = ERR_get_error();
@@ -172,6 +197,10 @@ struct HttpConn {
             strError = "TLS handshake failed with " + hostname + ": " + errBuf;
             return false;
         }
+        if (SSL_get_verify_result(ssl) != X509_V_OK) {
+            strError = "TLS certificate verification failed for " + hostname;
+            return false;
+        }
         return true;
     }
 };
@@ -229,13 +258,18 @@ bool DownloadFile(const std::string& host, const std::string& urlPath,
                   ProgressCallback progressFn,
                   std::string& strError,
                   bool noProxy,
-                  int portOverride)
+                  int portOverride,
+                  int64_t maxDownloadBytes)
 {
     try {
+        if (maxDownloadBytes <= 0) {
+            strError = "Download size limit must be positive";
+            return false;
+        }
         std::string currentHost = host;
         std::string currentPath = urlPath;
         int currentPort = (portOverride > 0) ? portOverride : PORT;
-        bool useSSL = false;
+        bool useSSL = (currentPort == 443);
         std::string headerData;
         int redirectCount = 0;
         const int MAX_REDIRECTS = 5;
@@ -324,11 +358,23 @@ bool DownloadFile(const std::string& host, const std::string& urlPath,
                 // Parse redirect URL — supports http://, https://, and relative paths
                 if (location.compare(0, 7, "http://") == 0 ||
                     location.compare(0, 8, "https://") == 0) {
-                    if (!ParseAbsoluteUrl(location, useSSL, currentHost,
-                                          currentPort, currentPath)) {
+                    bool redirectUsesSSL = false;
+                    std::string redirectHost;
+                    std::string redirectPath;
+                    int redirectPort = 0;
+                    if (!ParseAbsoluteUrl(location, redirectUsesSSL, redirectHost,
+                                          redirectPort, redirectPath)) {
                         strError = "Unsupported redirect location: " + location;
                         return false;
                     }
+                    if (useSSL && !redirectUsesSSL) {
+                        strError = "Refusing HTTPS downgrade redirect to " + location;
+                        return false;
+                    }
+                    useSSL = redirectUsesSSL;
+                    currentHost = redirectHost;
+                    currentPath = redirectPath;
+                    currentPort = redirectPort;
                 } else if (!location.empty() && location[0] == '/') {
                     currentPath = location;
                 } else {
@@ -362,6 +408,10 @@ bool DownloadFile(const std::string& host, const std::string& urlPath,
             if (lineEnd != std::string::npos)
                 content_length = std::stoll(headerData.substr(valStart, lineEnd - valStart));
         }
+        if (content_length < 0 || content_length > maxDownloadBytes) {
+            strError = "Download response exceeds the configured size limit";
+            return false;
+        }
 
         // Open output file
         FILE* file = fopen(destPath.string().c_str(), "wb");
@@ -385,7 +435,18 @@ bool DownloadFile(const std::string& host, const std::string& urlPath,
             }
             if (n == 0) break; // EOF
 
-            fwrite(chunk, 1, n, file);
+            if (bytes_written > maxDownloadBytes - n) {
+                fclose(file);
+                fs::remove(destPath);
+                strError = "Download response exceeded the configured size limit";
+                return false;
+            }
+            if (fwrite(chunk, 1, n, file) != static_cast<size_t>(n)) {
+                fclose(file);
+                fs::remove(destPath);
+                strError = "Failed writing bootstrap data to disk";
+                return false;
+            }
             bytes_written += n;
 
             if (progressFn && (bytes_written - last_progress >= 262144)) {
@@ -422,7 +483,8 @@ bool FetchFileList(const std::string& host,
     fs::path tmpPath = fs::temp_directory_path() / "triangles_bootstrap_filelist.txt";
 
     std::string urlPath = std::string(BASE_PATH) + "filelist.txt";
-    if (!DownloadFile(host, urlPath, tmpPath, nullptr, strError, noProxy))
+    if (!DownloadFile(host, urlPath, tmpPath, nullptr, strError, noProxy,
+                      -1, 1024 * 1024))
         return false;
 
     // Read lines
@@ -452,23 +514,6 @@ bool FetchFileList(const std::string& host,
 
 // --- tar.gz bootstrap support ---
 
-namespace {
-
-// Parse a tar octal field (ASCII octal, null/space terminated)
-static int64_t ParseTarOctal(const char* field, size_t len)
-{
-    int64_t result = 0;
-    for (size_t i = 0; i < len && field[i] != '\0' && field[i] != ' '; i++) {
-        if (field[i] < '0' || field[i] > '7') continue;
-        result = (result << 3) | (field[i] - '0');
-    }
-    return result;
-}
-
-// Extract a tar.gz file to a destination directory
-
-} // anonymous namespace
-
 bool ParseManifest(const fs::path& manifestPath,
                    SnapshotManifest& manifest,
                    std::string& strError)
@@ -575,12 +620,9 @@ bool VerifyManifest(const SnapshotManifest& manifest,
     }
 
     // ─── Signature verification (#11) ─────────────────────────────────────
-    // If the manifest includes a signature, verify it against the
-    // compiled-in snapshot signing key. This prevents MITM attacks
-    // where an attacker replaces the snapshot file on the bootstrap server.
-    //
-    // If no signature is present, print a warning but continue (backward
-    // compatibility with older snapshots that pre-date signing).
+    // Legacy pre-built indexes are never accepted without authentication.
+    // This format is disabled below, but keep its verifier fail-closed so a
+    // future caller cannot silently revive the old trust behavior.
     if (!manifest.signature.empty()) {
         // Build the message that was signed: "height||hash" (ASCII)
         std::string message = std::to_string(manifest.height) + "||" + manifest.hash;
@@ -656,12 +698,12 @@ bool VerifyManifest(const SnapshotManifest& manifest,
             strError = "Snapshot manifest signature INVALID — possible tampering detected";
             return false;
         } else {
-            // rc < 0 means error (e.g., placeholder zero pubkey not yet deployed)
-            printf("WARNING: Snapshot manifest signature verification error (rc=%d). "
-                   "Signing key may not be deployed yet. Proceeding without verification.\n", rc);
+            strError = "Snapshot manifest signature verification error";
+            return false;
         }
     } else {
-        printf("WARNING: Snapshot manifest has no signature — loading WITHOUT signature verification\n");
+        strError = "Snapshot manifest has no signature";
+        return false;
     }
 
     return true;
@@ -672,6 +714,13 @@ bool DownloadBootstrap(const std::string& host,
                        ProgressCallback progressFn,
                        std::string& strError)
 {
+    (void)host;
+    (void)dataDir;
+    (void)progressFn;
+    strError = "Legacy file-list bootstrap is disabled; use a compiled-hash UTXO snapshot or sync from genesis";
+    return false;
+
+#if 0
     bool gotBlockFile = false;
 
     // FastImport removed (commit bdb7253). v2 UTXO snapshot is the ONLY
@@ -758,8 +807,10 @@ bool DownloadBootstrap(const std::string& host,
         fs::remove(manifestPath);
 
     return true;
+#endif
 }
 
+#if 0
 namespace {
 
 // Try to find the canonical UTXO snapshot entry in the bootstrap server's
@@ -892,6 +943,7 @@ bool UnsetTrustedSnapshotPublisher(std::string& strError)
     fs::remove(filePath);
     return true;
 }
+#endif
 
 // Re-enter anonymous namespace for the remaining file-private helpers.
 // (IsTrustedSnapshotSigner / VerifySignedMessage / ExtractJsonString are
@@ -899,6 +951,7 @@ bool UnsetTrustedSnapshotPublisher(std::string& strError)
 
 namespace {
 
+#if 0
 bool IsTrustedSnapshotSigner(const std::string& addr)
 {
     // 1. Runtime override (set via RPC).
@@ -1072,6 +1125,7 @@ bool FindCanonicalSnapshotInManifest(const std::string& manifestText,
 
     return true;
 }
+#endif
 
 // Read an entire file into a string. Empty string on error.
 std::string ReadFileToString(const fs::path& path)
@@ -1114,6 +1168,80 @@ std::string Sha256OfFile(const fs::path& path)
 
 } // anonymous namespace
 
+namespace {
+
+bool IsHexString(const std::string& value, size_t expectedLength)
+{
+    if (value.size() != expectedLength)
+        return false;
+    for (unsigned char c : value) {
+        if (!std::isxdigit(c))
+            return false;
+    }
+    return true;
+}
+
+} // anonymous namespace
+
+bool ParseRemoteSnapshotManifest(const std::string& manifestText,
+                                 RemoteSnapshot& snapshot,
+                                 std::string& strError)
+{
+    snapshot = RemoteSnapshot{};
+
+    try {
+        const nlohmann::json root = nlohmann::json::parse(manifestText);
+        if (!root.is_object() || !root.contains("canonical") ||
+            !root.contains("files") || !root.contains("chain_tip")) {
+            strError = "manifest.json is missing canonical, files, or chain_tip";
+            return false;
+        }
+
+        snapshot.filename = root.at("canonical").at("snapshot").get<std::string>();
+        if (snapshot.filename.empty() || snapshot.filename == "." ||
+            snapshot.filename == ".." ||
+            snapshot.filename.find('/') != std::string::npos ||
+            snapshot.filename.find('\\') != std::string::npos) {
+            strError = "manifest snapshot filename must be a plain filename";
+            return false;
+        }
+
+        const nlohmann::json& files = root.at("files");
+        if (!files.is_object() || !files.contains(snapshot.filename)) {
+            strError = "canonical snapshot is absent from the files object";
+            return false;
+        }
+
+        const nlohmann::json& file = files.at(snapshot.filename);
+        const std::string type = file.at("type").get<std::string>();
+        if (type.rfind("utxo_snapshot", 0) != 0) {
+            strError = "canonical file is not a UTXO snapshot";
+            return false;
+        }
+
+        snapshot.sha256 = file.at("sha256").get<std::string>();
+        std::transform(snapshot.sha256.begin(), snapshot.sha256.end(),
+                       snapshot.sha256.begin(),
+                       [](unsigned char c) { return static_cast<char>(std::tolower(c)); });
+        snapshot.height = root.at("chain_tip").at("height").get<int>();
+        snapshot.blockHash = root.at("chain_tip").at("blockhash").get<std::string>();
+        std::transform(snapshot.blockHash.begin(), snapshot.blockHash.end(),
+                       snapshot.blockHash.begin(),
+                       [](unsigned char c) { return static_cast<char>(std::tolower(c)); });
+
+        if (snapshot.height <= 0 || !IsHexString(snapshot.sha256, 64) ||
+            !IsHexString(snapshot.blockHash, 64)) {
+            strError = "manifest snapshot height or hash fields are invalid";
+            return false;
+        }
+    } catch (const std::exception& e) {
+        strError = std::string("invalid manifest.json: ") + e.what();
+        return false;
+    }
+
+    return true;
+}
+
 bool DownloadUtxoSnapshot(const std::string& host,
                           const fs::path& dataDir,
                           ProgressCallback progressFn,
@@ -1121,79 +1249,51 @@ bool DownloadUtxoSnapshot(const std::string& host,
 {
     const bool noProxy = true;
 
-    // Step 1: discover the canonical snapshot filename + expected SHA256 +
-    // per-snapshot manifest filename from the big manifest.json. Falls back
-    // to legacy URL if manifest unavailable.
-    std::string snapshotFilename = "utxo-snapshot.bin";
-    std::string expectedSha256;
-    std::string snapshotManifestFilename;
-    bool haveManifest = false;
-
+    // manifest.json is discovery metadata, not a trust root. The only accepted
+    // snapshot hash is the one compiled into this release for the same height.
     fs::path tmpManifest = dataDir / "manifest.json.tmp";
-    if (DownloadFile(host, "manifest.json", tmpManifest, nullptr, strError, noProxy)) {
-        std::string text = ReadFileToString(tmpManifest);
+    if (!DownloadFile(host, std::string(BASE_PATH) + "manifest.json",
+                      tmpManifest, nullptr, strError, noProxy,
+                      -1, 4 * 1024 * 1024)) {
         fs::remove(tmpManifest);
-
-        std::string mFile, mSha, mManifest;
-        std::string mErr;
-        if (FindCanonicalSnapshotInManifest(text, mFile, mSha, mManifest, mErr)) {
-            snapshotFilename = mFile;
-            expectedSha256 = mSha;
-            snapshotManifestFilename = mManifest;
-            haveManifest = true;
-            printf("Bootstrap: manifest declares canonical snapshot %s (sha256=%s)\n",
-                   snapshotFilename.c_str(), expectedSha256.substr(0, 16).c_str());
-        } else {
-            printf("Bootstrap: manifest parse failed (%s) — falling back to legacy URL\n",
-                   mErr.c_str());
-        }
-    } else {
-        printf("Bootstrap: no manifest.json available — falling back to legacy URL\n");
-        strError.clear();
+        return false;
     }
 
-    // Step 2: verify the per-snapshot manifest's signature. This is the
-    // AUTHENTICATION gate — the signature attests that the listed snapshot
-    // file came from a trusted operator. No checkpoint required; signature
-    // alone proves authenticity.
-    if (!snapshotManifestFilename.empty()) {
-        fs::path tmpSnapManifest = dataDir / "snapshot-manifest.tmp";
-        if (!DownloadFile(host, snapshotManifestFilename, tmpSnapManifest, nullptr, strError, noProxy)) {
-            fs::remove(tmpSnapManifest);
-            return false;
-        }
-        std::string snapManifestText = ReadFileToString(tmpSnapManifest);
-        fs::remove(tmpSnapManifest);
-
-        std::string signerAddr = ExtractJsonString(snapManifestText, "signing_address");
-        std::string message     = ExtractJsonString(snapManifestText, "message");
-        std::string signature   = ExtractJsonString(snapManifestText, "signature");
-        std::string declaredSha = ExtractJsonString(snapManifestText, "snapshot_sha256");
-
-        if (signerAddr.empty() || message.empty() || signature.empty()) {
-            strError = "per-snapshot manifest missing required fields (signing_address/message/signature)";
-            return false;
-        }
-        if (!IsTrustedSnapshotSigner(signerAddr)) {
-            strError = "snapshot manifest signer " + signerAddr + " is not in trusted signers list";
-            return false;
-        }
-        std::string vErr;
-        if (!VerifySignedMessage(signerAddr, signature, message, vErr)) {
-            strError = "snapshot signature verification failed: " + vErr;
-            return false;
-        }
-        if (!declaredSha.empty())
-            expectedSha256 = declaredSha;
-        printf("Bootstrap: snapshot signature verified (signer=%s)\n", signerAddr.c_str());
-    } else {
-        printf("Bootstrap: WARNING — no per-snapshot manifest available; "
-               "loading snapshot WITHOUT signature verification\n");
+    const std::string manifestText = ReadFileToString(tmpManifest);
+    fs::remove(tmpManifest);
+    if (manifestText.empty()) {
+        strError = "Cannot read downloaded manifest.json";
+        return false;
     }
 
-    // Step 3: download the canonical snapshot file.
+    RemoteSnapshot snapshot;
+    if (!ParseRemoteSnapshotManifest(manifestText, snapshot, strError))
+        return false;
+
+    const uint256 manifestBlockHash(snapshot.blockHash);
+    if (!Checkpoints::IsKnownCheckpoint(snapshot.height, manifestBlockHash)) {
+        strError = "Server snapshot tip is not a hardened checkpoint in this release";
+        return false;
+    }
+
+    uint256 compiledFileHash;
+    if (!Checkpoints::GetSnapshotHash(snapshot.height, compiledFileHash)) {
+        strError = "Snapshot height " + std::to_string(snapshot.height) +
+                   " has no file hash compiled into this release";
+        return false;
+    }
+    const std::string compiledSha256 = compiledFileHash.ToString();
+    if (snapshot.sha256 != compiledSha256) {
+        strError = "Server snapshot hash does not match the hash compiled into this release";
+        return false;
+    }
+
+    printf("Bootstrap: manifest selects compiled snapshot %s at height %d (sha256=%s)\n",
+           snapshot.filename.c_str(), snapshot.height,
+           compiledSha256.substr(0, 16).c_str());
+
     fs::path tmpPath = dataDir / "utxo-snapshot.bin.tmp";
-    std::string urlPath = std::string(BASE_PATH) + snapshotFilename;
+    std::string urlPath = std::string(BASE_PATH) + snapshot.filename;
 
     printf("Bootstrap: downloading UTXO snapshot from %s%s...\n", host.c_str(), urlPath.c_str());
 
@@ -1202,30 +1302,25 @@ bool DownloadUtxoSnapshot(const std::string& host,
         return false;
     }
 
-    // Step 4: verify the downloaded file's SHA256 against the manifest.
-    if (!expectedSha256.empty()) {
-        std::string actualSha = Sha256OfFile(tmpPath);
-        if (actualSha.empty()) {
-            strError = "Cannot read downloaded snapshot for SHA256 verification";
-            fs::remove(tmpPath);
-            return false;
-        }
-        if (actualSha != expectedSha256) {
-            strError = "Snapshot SHA256 mismatch: expected " + expectedSha256
-                     + ", got " + actualSha
-                     + " (manifest/snapshot tampering or server misconfiguration)";
-            fs::remove(tmpPath);
-            return false;
-        }
-        printf("Bootstrap: snapshot SHA256 verified (%s)\n", actualSha.substr(0, 16).c_str());
+    const std::string actualSha256 = Sha256OfFile(tmpPath);
+    if (actualSha256.empty()) {
+        strError = "Cannot read downloaded snapshot for SHA256 verification";
+        fs::remove(tmpPath);
+        return false;
     }
+    if (actualSha256 != compiledSha256) {
+        strError = "Snapshot SHA256 does not match the hash compiled into this release";
+        fs::remove(tmpPath);
+        return false;
+    }
+    printf("Bootstrap: compiled snapshot SHA256 verified (%s)\n",
+           actualSha256.substr(0, 16).c_str());
 
     printf("Bootstrap: UTXO snapshot downloaded, loading into database...\n");
 
-    // Step 5: load the snapshot. requireCheckpoint is FALSE — signature is
-    // the authentication gate; checkpoints would force snapshots only at
-    // specific heights. Signature alone is sufficient.
-    if (!UtxoSnapshot::LoadSnapshot(tmpPath, dataDir, strError, /*requireCheckpoint=*/false)) {
+    // File hash and tip checkpoint are independent gates. The hash commits to
+    // the complete serialized UTXO set; the checkpoint commits to chain identity.
+    if (!UtxoSnapshot::LoadSnapshot(tmpPath, dataDir, strError, /*requireCheckpoint=*/true)) {
         fs::remove(tmpPath);
         return false;
     }
diff --git a/src/bootstrap.h b/src/bootstrap.h
index 07ee873..80baa5b 100644
--- a/src/bootstrap.h
+++ b/src/bootstrap.h
@@ -8,13 +8,14 @@
 #include <vector>
 #include <functional>
 #include <filesystem>
+#include <cstdint>
 
 namespace Bootstrap {
 
     // Bootstrap server configuration
-    static const char* DEFAULT_HOST = "bootstrap.cryptographic-triangles.org";
-    static const char* BASE_PATH = "/";
-    static const int PORT = 80;
+    inline constexpr const char* DEFAULT_HOST = "bootstrap.cryptographic-triangles.org";
+    inline constexpr const char* BASE_PATH = "/";
+    inline constexpr int PORT = 443;
 
     // Progress callback: (bytesDownloaded, totalBytes)
     typedef std::function<void(int64_t, int64_t)> ProgressCallback;
@@ -31,7 +32,8 @@ namespace Bootstrap {
                       ProgressCallback progressFn,
                       std::string& strError,
                       bool noProxy = false,
-                      int portOverride = -1);
+                      int portOverride = -1,
+                      int64_t maxDownloadBytes = 4LL * 1024 * 1024 * 1024);
 
     // Fetch the file manifest (list of relative paths to download)
     bool FetchFileList(const std::string& host,
@@ -46,6 +48,23 @@ namespace Bootstrap {
                            ProgressCallback progressFn,
                            std::string& strError);
 
+    // Advertised identity of a snapshot listed by manifest.json.
+    // The advertised SHA256 is accepted only when it matches the hash compiled
+    // into checkpoints.cpp for the same height.
+    struct RemoteSnapshot {
+        std::string filename;
+        std::string sha256;
+        int height;
+        std::string blockHash;
+    };
+
+    // Parse and validate the small, untrusted bootstrap manifest. This routine
+    // performs no network I/O and is exposed so malformed-input behavior can be
+    // covered by unit tests.
+    bool ParseRemoteSnapshotManifest(const std::string& manifestText,
+                                     RemoteSnapshot& snapshot,
+                                     std::string& strError);
+
     // Snapshot manifest (parsed from snapshot.manifest in bootstrap archive)
     struct SnapshotManifest {
         int format;            // format version, must be 1
@@ -73,27 +92,6 @@ namespace Bootstrap {
                               ProgressCallback progressFn,
                               std::string& strError);
 
-    // ===================================================================
-    // Trusted snapshot publisher — RPC-driven single-slot rotation
-    // ===================================================================
-    // Returns the currently active trusted publisher, or empty string if
-    // only the built-in fallback is in effect.
-    std::string GetActiveTrustedSnapshotPublisher();
-
-    // Atomically replaces the active publisher. The previous one is dropped
-    // immediately (Design A: single-slot, no grace period). Persists to
-    // <datadir>/snapshot-publisher.json so the choice survives restarts.
-    bool SetTrustedSnapshotPublisher(const std::string& addr,
-                                     std::string& strError);
-
-    // Clears the runtime override and reverts to the built-in fallback
-    // list. Also removes snapshot-publisher.json from disk.
-    bool UnsetTrustedSnapshotPublisher(std::string& strError);
-
-    // Called once at daemon startup (from init.cpp) to load any persisted
-    // runtime override.
-    void LoadTrustedSnapshotPublisher();
-
 } // namespace Bootstrap
 
 #endif // TRIANGLES_BOOTSTRAP_H
diff --git a/src/checkpointpublisher.cpp b/src/checkpointpublisher.cpp
index 8a0ca8b..910f242 100644
--- a/src/checkpointpublisher.cpp
+++ b/src/checkpointpublisher.cpp
@@ -425,7 +425,8 @@ bool LoadSignedCheckpoints(
     if (Bootstrap::DownloadFile(host, "signed-checkpoints.json",
                                  std::filesystem::temp_directory_path() / "signed-checkpoints.json.tmp",
                                  nullptr, strError,
-                                 /*noProxy=*/true)) {
+                                 /*noProxy=*/true, /*portOverride=*/-1,
+                                 /*maxDownloadBytes=*/10 * 1024 * 1024)) {
         std::filesystem::path tmp = std::filesystem::temp_directory_path() / "signed-checkpoints.json.tmp";
         FILE* f = fopen(tmp.string().c_str(), "rb");
         if (f) {
diff --git a/src/checkpoints.cpp b/src/checkpoints.cpp
index 765d156..8c644ba 100644
--- a/src/checkpoints.cpp
+++ b/src/checkpoints.cpp
@@ -353,53 +353,14 @@ namespace Checkpoints
 
     bool SetCheckpointPrivKey(std::string strPrivKey)
     {
-        // Test signing a sync-checkpoint with genesis block
-        CSyncCheckpoint checkpoint;
-        checkpoint.hashCheckpoint = !fTestNet ? hashGenesisBlockOfficial : hashGenesisBlockTestNet;
-        CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
-        sMsg << (CUnsignedSyncCheckpoint)checkpoint;
-        checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
-
-        std::vector<unsigned char> vchPrivKey = ParseHex(strPrivKey);
-        CKey key;
-        key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
-        if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
-            return false;
-
-        // Test signing successful, proceed
-        CSyncCheckpoint::strMasterPrivKey = strPrivKey;
-        return true;
+        (void)strPrivKey;
+        return error("SetCheckpointPrivKey: synchronized checkpoints are disabled");
     }
 
     bool SendSyncCheckpoint(uint256 hashCheckpoint)
     {
-        CSyncCheckpoint checkpoint;
-        checkpoint.hashCheckpoint = hashCheckpoint;
-        CDataStream sMsg(SER_NETWORK, PROTOCOL_VERSION);
-        sMsg << (CUnsignedSyncCheckpoint)checkpoint;
-        checkpoint.vchMsg = std::vector<unsigned char>(sMsg.begin(), sMsg.end());
-
-        if (CSyncCheckpoint::strMasterPrivKey.empty())
-            return error("SendSyncCheckpoint: Checkpoint master key unavailable.");
-        std::vector<unsigned char> vchPrivKey = ParseHex(CSyncCheckpoint::strMasterPrivKey);
-        CKey key;
-        key.SetPrivKey(CPrivKey(vchPrivKey.begin(), vchPrivKey.end())); // if key is not correct openssl may crash
-        if (!key.Sign(Hash(checkpoint.vchMsg.begin(), checkpoint.vchMsg.end()), checkpoint.vchSig))
-            return error("SendSyncCheckpoint: Unable to sign checkpoint, check private key?");
-
-        if(!checkpoint.ProcessSyncCheckpoint(nullptr))
-        {
-            printf("WARNING: SendSyncCheckpoint: Failed to process checkpoint.\n");
-            return false;
-        }
-
-        // Relay checkpoint
-        {
-            LOCK(cs_vNodes);
-            for (CNode* pnode : vNodes)
-                checkpoint.RelayTo(pnode);
-        }
-        return true;
+        (void)hashCheckpoint;
+        return error("SendSyncCheckpoint: synchronized checkpoints are disabled");
     }
 
     // Is the sync-checkpoint outside maturity window?
@@ -420,13 +381,11 @@ const std::string CSyncCheckpoint::strMasterPubKey = "";
 std::string CSyncCheckpoint::strMasterPrivKey = "";
 
 // triangles: verify signature of sync-checkpoint message
-// Master key system disabled - checkpoint signatures are no longer required
+// The master-key system is disabled. Reject these legacy messages instead of
+// treating unsigned data as authenticated if a dispatcher is added later.
 bool CSyncCheckpoint::CheckSignature()
 {
-    // Deserialize the checkpoint data without signature verification
-    CDataStream sMsg(vchMsg, SER_NETWORK, PROTOCOL_VERSION);
-    sMsg >> *(CUnsignedSyncCheckpoint*)this;
-    return true;
+    return error("CSyncCheckpoint::CheckSignature: synchronized checkpoints are disabled");
 }
 
 // triangles: process synchronized checkpoint
diff --git a/src/init.cpp b/src/init.cpp
index 20f03ed..9d93284 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -30,8 +30,11 @@
 #include "addressindex.h"
 #include "chaindb_migrate.h"
 #include <memory>
+#include <atomic>
+#include <cstdlib>
 #include <thread>
 #include <vector>
+#include <cerrno>
 
 // Forward declaration: InitError / InitWarning are defined further down
 // in this file but referenced by AppInit (line ~423) before the definition.
@@ -66,6 +69,8 @@ using namespace std;
 namespace fs = std::filesystem;
 
 namespace {
+std::atomic<int> g_shutdownExitCode{EXIT_SUCCESS};
+
 // Acquire an exclusive, non-blocking advisory lock on the datadir .lock file
 // and hold it for the lifetime of the process. Replaces
 // boost::interprocess::file_lock. The descriptor/handle is intentionally never
@@ -96,8 +101,32 @@ bool LockDataDirectory(const std::filesystem::path& pathLockFile)
     return true; // fd held until process exit
 #endif
 }
+
+#ifndef WIN32
+bool EnsureOwnerOnlyFile(const std::filesystem::path& path, std::string& error)
+{
+    struct stat fileStat;
+    if (::lstat(path.string().c_str(), &fileStat) != 0)
+        return errno == ENOENT;
+    if (!S_ISREG(fileStat.st_mode) || fileStat.st_uid != geteuid()) {
+        error = path.string() + " must be a regular file owned by the daemon user";
+        return false;
+    }
+    if ((fileStat.st_mode & (S_IRWXG | S_IRWXO)) != 0 &&
+        ::chmod(path.string().c_str(), S_IRUSR | S_IWUSR) != 0) {
+        error = "could not restrict permissions on " + path.string();
+        return false;
+    }
+    return true;
+}
+#endif
 } // namespace
 
+void MarkShutdownFailure()
+{
+    g_shutdownExitCode.store(EXIT_FAILURE, std::memory_order_relaxed);
+}
+
 std::unique_ptr<CWallet> pwalletMain;
 CClientUIInterface uiInterface;
 std::string strWalletFileName;
@@ -144,7 +173,8 @@ void ExitTimeout(void* parg)
 {
 #ifdef WIN32
     MilliSleep(5000);
-    ExitProcess(0);
+    ExitProcess(static_cast<UINT>(
+        g_shutdownExitCode.load(std::memory_order_relaxed)));
 #endif
 }
 
@@ -421,7 +451,11 @@ void Shutdown(void* parg)
 //        MakeChainDB()->Close();
         bitdb.Flush(false);
         bitdb.Flush(true);
-        fs::remove(GetPidFile());
+        std::error_code pidFileError;
+        fs::remove(GetPidFile(), pidFileError);
+        if (pidFileError)
+            printf("Warning: could not remove PID file: %s\n",
+                   pidFileError.message().c_str());
         UnregisterWallet(pwalletMain.get());
         pwalletMain.reset();
         // DB is flushed and wallet saved - safe to force-exit if something hangs
@@ -431,7 +465,7 @@ void Shutdown(void* parg)
         fExit = true;
 #ifndef QT_GUI
         // ensure non-UI client gets exited here, but let Triangles-Qt reach 'return 0;' in triangles.cpp
-        exit(0);
+        exit(g_shutdownExitCode.load(std::memory_order_relaxed));
 #endif
     }
     else
@@ -528,8 +562,10 @@ bool AppInit(int argc, char* argv[])
     } catch (...) {
         PrintException(nullptr, "AppInit()");
     }
-    if (!fRet)
+    if (!fRet) {
+        MarkShutdownFailure();
         Shutdown(nullptr);
+    }
     return fRet;
 }
 
@@ -610,8 +646,8 @@ std::string HelpMessage()
         //"  -onlynet=<net>         " + _("Only connect to nodes in network <net> (IPv4, IPv6 or Tor)") + "\n" +
         //"  -discover              " + _("Discover own IP address (default: 1 when listening and no -externalip)") + "\n" +
         //"  -irc                   " + _("Find peers using internet relay chat (default: 0)") + "\n" +
-        //"  -listen                " + _("Accept connections from outside (default: 1 if no -proxy or -connect)") + "\n" +
-        //"  -bind=<addr>           " + _("Bind to given address. Use [host]:port notation for IPv6") + "\n" +
+        "  -listen                " + _("Accept inbound peer connections (default: 1 unless -proxy or -connect is set)") + "\n" +
+        "  -bind=<addr>           " + _("Bind inbound peers to this address. Use [host]:port notation for IPv6") + "\n" +
         //  -dnsseed               " + _("Find peers using DNS lookup (default: 1)") + "\n" +
         "  -staking               " + _("Stake your coins to support network and gain reward (default: 1)") + "\n" +
         "  -synctime              " + _("Sync time with other nodes. Disable if time on your system is precise e.g. syncing with NTP (default: 1)") + "\n" +
@@ -652,8 +688,11 @@ std::string HelpMessage()
 #endif
         "  -rpcuser=<user>        " + _("Username for JSON-RPC connections") + "\n" +
         "  -rpcpassword=<pw>      " + _("Password for JSON-RPC connections") + "\n" +
-        "  -rpcport=<port>        " + _("Listen for JSON-RPC connections on <port> (default: 19111 or testnet: 19112)") + "\n" +
-        "  -rpcallowip=<ip>       " + _("Allow JSON-RPC connections from specified IP address") + "\n" +
+        "  -rpcport=<port>        " + _("Listen for JSON-RPC connections on <port> (default: 19112 or testnet: 19111)") + "\n" +
+        "  -rpcbind=<addr>        " + _("Bind JSON-RPC to this address (default: loopback only; use * explicitly for all interfaces)") + "\n" +
+        "  -rpcallowip=<ip>       " + _("Allow JSON-RPC clients matching this address pattern; does not change the bind address") + "\n" +
+        "  -rpcallowmethod=<name> " + _("Allow only this JSON-RPC method (repeat for each method; default: all)") + "\n" +
+        "  -rpcservertimeout=<n>  " + _("RPC socket read/write timeout in seconds (default: 30, range: 1-600)") + "\n" +
         "  -rpcconnect=<ip>       " + _("Send commands to node running on <ip> (default: 127.0.0.1)") + "\n" +
         "  -blocknotify=<cmd>     " + _("Execute command when the best block changes (%s in cmd is replaced by block hash)") + "\n" +
         "  -walletnotify=<cmd>    " + _("Execute command when a wallet transaction changes (%s in cmd is replaced by TxID)") + "\n" +
@@ -1120,24 +1159,19 @@ bool AppInit2()
     fUseUPnP = GetBoolArg("-upnp", USE_UPNP);
 #endif
     bool fBound = false;
-    if (true) {
-        if (true) {
-            do {
-                // W1: Bind to all interfaces so external peers can connect.
-                //
-                // The previous code went through Lookup("0.0.0.0", ...) which
-                // hands the literal string to getaddrinfo(). On Windows that
-                // resolver can fail to map "0.0.0.0" to INADDR_ANY and the
-                // daemon would abort at startup with "Cannot resolve binding
-                // address". Construct the CService directly from INADDR_ANY
-                // instead — this is the canonical "any-address" binding and
-                // works on every platform without consulting the resolver.
+    if (!fNoListen) {
+        if (mapArgs.count("-bind")) {
+            for (const std::string& bindAddress : mapMultiArgs["-bind"]) {
                 CService addrBind;
-                struct in_addr any;
-                any.s_addr = htonl(INADDR_ANY);
-                addrBind = CService(any, GetListenPort());
+                if (!Lookup(bindAddress.c_str(), addrBind, GetListenPort(), false))
+                    return InitError(strprintf(_("Cannot resolve -bind address: '%s'"),
+                                               bindAddress.c_str()));
                 fBound |= Bind(addrBind);
-            } while (false);
+            }
+        } else {
+            struct in_addr any;
+            any.s_addr = htonl(INADDR_ANY);
+            fBound = Bind(CService(any, GetListenPort()));
         }
         if (!fBound)
             return InitError(_("Failed to listen on any port."));
@@ -1167,10 +1201,9 @@ bool AppInit2()
         }
     }
 
-   if (mapArgs.count("-checkpointkey")) // triangles: checkpoint master priv key
+    if (mapArgs.count("-checkpointkey"))
     {
-        if (!Checkpoints::SetCheckpointPrivKey(GetArg(std::string_view{"-checkpointkey"}, std::string_view{""})))
-            InitError(_("Unable to sign checkpoint, wrong checkpointkey?\n"));
+        return InitError(_("Synchronized checkpoint signing is disabled."));
     }
 
     for (string strDest : mapMultiArgs["-seednode"])
@@ -1178,8 +1211,8 @@ bool AppInit2()
     StartupPerfLog("network_init", GetTimeMillis() - nStart, strprintf("listen=%d seednodes=%" PRIszu, !fNoListen, mapMultiArgs["-seednode"].size()));
 
     // ********************************************************* Step 6b: bootstrap download (daemon)
-    // Automatic: if data dir has no blockchain, bootstrap without asking.
-    // Can also be forced with -bootstrap flag, or disabled with -nobootstrap.
+    // Remote HTTP bootstrap is opt-in via -bootstrap. Fresh nodes otherwise
+    // use the compiled-hash P2P snapshot path or sync from genesis.
     //
     // v5.9.5: P2P UTXO snapshot fetch is the default for fresh installs (Step 11.6).
     // The legacy clearnet HTTP bootstrap only runs when the user explicitly requests
@@ -1187,20 +1220,13 @@ bool AppInit2()
 // Bootstrap auto-download works for both GUI and daemon.
     // GUI users get the same automatic bootstrap on fresh installs.
     {
-        bool wantsBootstrap = GetBoolArg("-bootstrap", false);
         bool noBootstrap = GetBoolArg("-nobootstrap", false);
-        bool snapshotMode = GetBoolArg("-snapshot", true);
+        bool wantsBootstrap = GetBoolArg("-bootstrap", false) && !noBootstrap;
         fs::path dataPath = GetDataDir();
-        // Load any runtime trusted snapshot publisher override that was
-        // persisted by a previous settrustedv2snapshotpublisher call.
-        Bootstrap::LoadTrustedSnapshotPublisher();
         bool needsBootstrap = Bootstrap::NeedsBootstrap(dataPath);
 
-        if (needsBootstrap && !noBootstrap) {
-            printf("Bootstrap: no blockchain data found — downloading UTXO snapshot automatically.\n");
-            printf("Bootstrap: (use -nobootstrap to skip)\n");
-            uiInterface.InitMessage(_("Downloading UTXO snapshot..."));
-            wantsBootstrap = true;
+        if (needsBootstrap && !wantsBootstrap) {
+            printf("Bootstrap: no blockchain data found; remote bootstrap is disabled unless -bootstrap is set.\n");
         }
 
     if (wantsBootstrap)
@@ -1208,7 +1234,6 @@ bool AppInit2()
         int64_t nBootstrapStart = GetTimeMillis();
         fs::path dataPath = GetDataDir();
         std::string host = Bootstrap::DEFAULT_HOST;
-        std::string strError;
 
         int64_t lastGuiUpdate = 0;
         auto progressFn = [&lastGuiUpdate](int64_t bytesDownloaded, int64_t totalBytes) {
@@ -1250,19 +1275,10 @@ bool AppInit2()
             triedUtxoSnapshot = true;
         }
 
-        // Fall back to full bootstrap.tar.gz if UTXO snapshot failed
+        // Never consume a server-directed file list. If the authenticated
+        // snapshot is unavailable, normal peer-to-peer sync is the safe fallback.
         if (!success) {
-            uiInterface.InitMessage(_("Downloading blockchain snapshot..."));
-            printf("Bootstrap: contacting %s...\n", host.c_str());
-
-            success = Bootstrap::DownloadBootstrap(host, dataPath, progressFn, strError);
-
-            if (!success) {
-                printf("\nBootstrap: failed: %s\n", strError.c_str());
-                printf("Bootstrap: skipping, will sync from network.\n");
-            } else {
-                printf("\nBootstrap: done.\n");
-            }
+            printf("Bootstrap: no trusted compiled-hash snapshot available; syncing from peers.\n");
         }
 
         StartupPerfLog("bootstrap_download", GetTimeMillis() - nBootstrapStart,
@@ -1282,13 +1298,23 @@ bool AppInit2()
             printf("Found utxo-snapshot.bin — loading UTXO snapshot...\n");
             uiInterface.InitMessage(_("Loading UTXO snapshot..."));
 
-            // Local file load: skip the checkpoint gate. The operator has
-            // filesystem access, so the trust model is already equivalent
-            // to direct chain state modification — a malicious local file
-            // is no worse than a malicious chain DB. P2P-delivered
-            // snapshots (SnapshotNet) keep the checkpoint gate on.
             std::string strError;
-            if (UtxoSnapshot::LoadSnapshot(snapshotFile, dataPath, strError, /*requireCheckpoint=*/false)) {
+            const int snapshotHeight = Checkpoints::GetBestSnapshotHeight();
+            uint256 compiledHash;
+            uint256 actualHash;
+            const bool hasCompiledHash = snapshotHeight > 0 &&
+                Checkpoints::GetSnapshotHash(snapshotHeight, compiledHash);
+            const bool hashVerified = hasCompiledHash &&
+                SnapshotNet::ComputeSnapshotFileHash(snapshotFile, actualHash, strError) &&
+                actualHash == compiledHash;
+
+            if (!hashVerified) {
+                if (strError.empty())
+                    strError = "snapshot SHA256 is not compiled into this release";
+                printf("UTXO snapshot rejected before import: %s\n", strError.c_str());
+                printf("Will proceed with normal sync.\n");
+            } else if (UtxoSnapshot::LoadSnapshot(snapshotFile, dataPath, strError,
+                                                   /*requireCheckpoint=*/true)) {
                 printf("UTXO snapshot loaded successfully.\n");
             } else {
                 printf("UTXO snapshot load failed: %s\n", strError.c_str());
@@ -1501,6 +1527,11 @@ bool AppInit2()
     {
         fs::path walletPath = GetDataDir() / strWalletFileName;
         if (fs::exists(walletPath)) {
+#ifndef WIN32
+            std::string permissionError;
+            if (!EnsureOwnerOnlyFile(walletPath, permissionError))
+                return InitError(permissionError);
+#endif
             uintmax_t wsize = fs::file_size(walletPath);
             printf("Wallet file size: %llu bytes\n", (unsigned long long)wsize);
             if (wsize < 1024) {
@@ -1933,10 +1964,10 @@ bool AppInit2()
     printf("mapAddressBook.size() = %" PRIszu "\n",  pwalletMain->mapAddressBook.size());
 
     if (!NewThread(StartNode, nullptr))
-        InitError(_("Error: could not start node"));
+        return InitError(_("Error: could not start node"));
 
-    if (fServer)
-        NewThread(ThreadRPCServer, nullptr);
+    if (fServer && !NewThread(ThreadRPCServer, nullptr))
+        return InitError(_("Error: could not start the RPC server"));
 
     // ********************************************************* Step 11.6: P2P UTXO snapshot fetch
     // If the chain is empty and snapshot mode is enabled (default), spawn a
diff --git a/src/init.h b/src/init.h
index 4f91850..d4181b3 100644
--- a/src/init.h
+++ b/src/init.h
@@ -12,6 +12,7 @@
 extern std::unique_ptr<CWallet> pwalletMain;
 extern std::string strWalletFileName;
 void StartShutdown();
+void MarkShutdownFailure();
 bool ShutdownRequested();
 void Shutdown(void* parg);
 bool AppInit2();
@@ -19,4 +20,3 @@ std::string HelpMessage();
 
 #endif
 
-
diff --git a/src/keystore.cpp b/src/keystore.cpp
index dc3223a..4d759d1 100644
--- a/src/keystore.cpp
+++ b/src/keystore.cpp
@@ -190,28 +190,49 @@ bool CCryptoKeyStore::GetPubKey(const CKeyID &address, CPubKey& vchPubKeyOut) co
     return false;
 }
 
-bool CCryptoKeyStore::EncryptKeys(CKeyingMaterial& vMasterKeyIn)
+bool CCryptoKeyStore::PrepareKeyEncryption(CKeyingMaterial& vMasterKeyIn,
+                                           CryptedKeyMap& cryptedKeysOut) const
 {
-    {
-        LOCK(cs_KeyStore);
-        if (!mapCryptedKeys.empty() || IsCrypted())
-            return false;
+    LOCK(cs_KeyStore);
+    if (!mapCryptedKeys.empty() || IsCrypted())
+        return false;
 
-        fUseCrypto = true;
-        for (KeyMap::value_type& mKey : mapKeys)
-        {
-            CKey key;
-            if (!key.SetSecret(mKey.second.first, mKey.second.second))
-                return false;
-            const CPubKey vchPubKey = key.GetPubKey();
-            std::vector<unsigned char> vchCryptedSecret;
-            bool fCompressed;
-            if (!EncryptSecret(vMasterKeyIn, key.GetSecret(fCompressed), vchPubKey.GetHash(), vchCryptedSecret))
-                return false;
-            if (!AddCryptedKey(vchPubKey, vchCryptedSecret))
-                return false;
-        }
-        mapKeys.clear();
+    cryptedKeysOut.clear();
+    for (const KeyMap::value_type& mKey : mapKeys)
+    {
+        CKey key;
+        if (!key.SetSecret(mKey.second.first, mKey.second.second))
+            return false;
+        const CPubKey vchPubKey = key.GetPubKey();
+        std::vector<unsigned char> vchCryptedSecret;
+        bool fCompressed;
+        if (!EncryptSecret(vMasterKeyIn, key.GetSecret(fCompressed),
+                           vchPubKey.GetHash(), vchCryptedSecret))
+            return false;
+        if (!cryptedKeysOut.emplace(vchPubKey.GetID(),
+                                    std::make_pair(vchPubKey,
+                                                   std::move(vchCryptedSecret))).second)
+            return false;
     }
+    return cryptedKeysOut.size() == mapKeys.size();
+}
+
+bool CCryptoKeyStore::CommitKeyEncryption(CryptedKeyMap&& cryptedKeys)
+{
+    LOCK(cs_KeyStore);
+    if (!mapCryptedKeys.empty() || IsCrypted() || cryptedKeys.size() != mapKeys.size())
+        return false;
+
+    mapCryptedKeys = std::move(cryptedKeys);
+    mapKeys.clear();
+    fUseCrypto = true;
     return true;
 }
+
+bool CCryptoKeyStore::EncryptKeys(CKeyingMaterial& vMasterKeyIn)
+{
+    CryptedKeyMap cryptedKeys;
+    if (!PrepareKeyEncryption(vMasterKeyIn, cryptedKeys))
+        return false;
+    return CommitKeyEncryption(std::move(cryptedKeys));
+}
diff --git a/src/keystore.h b/src/keystore.h
index 4fb2523..fbfb869 100644
--- a/src/keystore.h
+++ b/src/keystore.h
@@ -9,6 +9,8 @@
 #include "util_signal.h"
 #include "sync.h"
 
+#include <utility>
+
 class CScript;
 
 /** A virtual base class for key stores */
@@ -112,7 +114,13 @@ protected:
 
     bool SetCrypted();
 
-    // will encrypt previously unencrypted keys
+    // Stage and commit wallet-key encryption separately so callers can make
+    // the on-disk update atomic before discarding plaintext keys in memory.
+    bool PrepareKeyEncryption(CKeyingMaterial& vMasterKeyIn,
+                              CryptedKeyMap& cryptedKeysOut) const;
+    bool CommitKeyEncryption(CryptedKeyMap&& cryptedKeys);
+
+    // Encrypt previously unencrypted keys in memory.
     bool EncryptKeys(CKeyingMaterial& vMasterKeyIn);
 
     bool Unlock(const CKeyingMaterial& vMasterKeyIn);
diff --git a/src/main.cpp b/src/main.cpp
index 734e2f1..fc6a46d 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1747,6 +1747,11 @@ bool IsConsensusAssumeValidHeight(int nHeight)
         || (nHeight <= nAssumeValidThreshold);
 }
 
+bool IsBlockSignatureRequiredAtHeight(int nHeight)
+{
+    return nHeight > Checkpoints::GetTotalBlocksEstimate();
+}
+
 void static InvalidChainFound(CBlockIndex* pindexNew)
 {
     if (pindexNew->nChainTrust > nBestInvalidTrust)
@@ -3401,6 +3406,12 @@ bool CBlock::AcceptBlock()
     uint256 hashProofOfStake = 0, targetProofOfStake = 0;
     if (IsProofOfStake())
     {
+        // The rolling validation optimization is not a signature trust root.
+        // Every PoS block above the compiled checkpoint must authorize its
+        // exact block contents, including while the local tip is stale.
+        if (IsBlockSignatureRequiredAtHeight(nHeight) && !CheckBlockSignature())
+            return DoS(100, error("AcceptBlock() : bad proof-of-stake block signature at height %d", nHeight));
+
         if (IsConsensusAssumeValidHeight(nHeight))
         {
             // Historical fast path: blocks at/below hardcoded checkpoint or
@@ -3539,10 +3550,16 @@ bool ProcessBlock(CNode* pfrom, CBlock* pblock)
     if (pblock->IsProofOfStake() && !GetBoolArg("-ignoredupstake", false) && setStakeSeen.count(pblock->GetProofOfStake()) && !mapOrphanBlocksByPrev.count(hash))
         return error("ProcessBlock() : duplicate proof-of-stake (%s, %d) for block %s", pblock->GetProofOfStake().first.ToString().c_str(), pblock->GetProofOfStake().second, hash.ToString().c_str());
 
-    // Preliminary checks
-    // Skip block signature verification during initial block download (below checkpoint).
-    // The hardcoded checkpoint guarantees historical chain integrity.
-    if (!pblock->CheckBlock(true, true, !IsInitialBlockDownload()))
+    // Operational IBD state is never permission to skip a live proof-of-stake
+    // block signature. Only a candidate height committed by the latest
+    // hardened checkpoint uses the historical fast path.
+    bool checkBlockSignature = true;
+    const auto prevIt = mapBlockIndex.find(pblock->hashPrevBlock);
+    if (prevIt != mapBlockIndex.end()) {
+        const int candidateHeight = prevIt->second->nHeight + 1;
+        checkBlockSignature = IsBlockSignatureRequiredAtHeight(candidateHeight);
+    }
+    if (!pblock->CheckBlock(true, true, checkBlockSignature))
     {
         printf("IBD-DIAG: CheckBlock FAILED for %s (PoS=%d, IBD=%d)\n",
             hash.ToString().substr(0,20).c_str(), pblock->IsProofOfStake(), IsInitialBlockDownload());
@@ -3786,6 +3803,7 @@ bool CheckDiskSpace(uint64_t nAdditionalBytes)
         strMiscWarning = strMessage;
         printf("*** %s\n", strMessage.c_str());
         uiInterface.ThreadSafeMessageBox(strMessage, "Triangles", CClientUIInterface::OK | CClientUIInterface::ICON_EXCLAMATION | CClientUIInterface::MODAL);
+        MarkShutdownFailure();
         StartShutdown();
         return false;
     }
@@ -6039,5 +6057,3 @@ bool SendMessages(CNode* pto, bool fSendTrickle)
     }
     return true;
 }
-
-
diff --git a/src/main.h b/src/main.h
index ec06932..55fc5fd 100644
--- a/src/main.h
+++ b/src/main.h
@@ -176,6 +176,7 @@ bool IsStakingSafe(const CWallet* pwallet, const std::vector<CNode*>& vNodesSnap
 // assume-valid validation. This intentionally excludes operational IBD states
 // such as a stale tip; stale-tip IBD must not disable live PoS checks.
 [[nodiscard]] bool IsConsensusAssumeValidHeight(int nHeight);
+[[nodiscard]] bool IsBlockSignatureRequiredAtHeight(int nHeight);
 std::string GetWarnings(std::string strFor);
 bool GetTransaction(const uint256 &hash, CTransaction &tx, uint256 &hashBlock);
 uint256 WantedByOrphan(const CBlock* pblockOrphan);
diff --git a/src/net.cpp b/src/net.cpp
index 58389fb..843febf 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -605,7 +605,8 @@ CNode* ConnectNode(CAddress addrConnect, const char *pszDest)
     }
 
     if (fDebug) {
-         printf("ConnectNode(): pszDest: %s\n", pszDest);
+         printf("ConnectNode(): destination: %s\n",
+                pszDest ? pszDest : addrConnect.ToString().c_str());
     }
 
     /// debug print
@@ -1738,7 +1739,7 @@ void ThreadOnionSeed(void* parg)
 
     // Fetch dynamic seeds with retry — up to 4 attempts with increasing backoff.
     // This is the primary discovery mechanism — seeds.cryptographic-triangles.org
-    {
+    if (!GetBoolArg("-noseedurl", false)) {
         bool ok = false;
         int delays[] = {0, 30, 60, 120};
         for (int attempt = 0; attempt < 4 && !ok && !fShutdown; attempt++) {
@@ -1806,7 +1807,8 @@ void ThreadOnionSeed(void* parg)
             else
                 printf("ThreadOnionSeed: low outbound peers (%d), re-seeding...\n", nOutbound);
 
-            ThreadHTTPSeedFetch2(nullptr);
+            if (!GetBoolArg("-noseedurl", false))
+                ThreadHTTPSeedFetch2(nullptr);
 
             // Re-queue hardcoded seeds for direct connection
             for (unsigned int seed_idx = 0; strOnionSeed[seed_idx][0] != nullptr; seed_idx++) {
@@ -1891,6 +1893,12 @@ bool ThreadHTTPSeedFetch2(void* parg)
         seedPath = seedHost.substr(slashPos);
         seedHost = seedHost.substr(0, slashPos);
     }
+    if (seedHost.empty() || seedHost.find_first_of("\r\n") != std::string::npos ||
+        seedPath.empty() || seedPath[0] != '/' ||
+        seedPath.find_first_of("\r\n") != std::string::npos) {
+        printf("HTTPS seed fetch: invalid -seedurl value\n");
+        return false;
+    }
 
     printf("Fetching seed list from https://%s%s (via Tor)...\n", seedHost.c_str(), seedPath.c_str());
 
@@ -1929,7 +1937,14 @@ bool ThreadHTTPSeedFetch2(void* parg)
         }
 
         // Set SNI hostname (required for Caddy/Let's Encrypt)
-        SSL_set_tlsext_host_name(ssl, seedHost.c_str());
+        if (SSL_set_tlsext_host_name(ssl, seedHost.c_str()) != 1 ||
+            SSL_set1_host(ssl, seedHost.c_str()) != 1) {
+            printf("HTTPS seed fetch: failed to configure TLS hostname verification\n");
+            SSL_free(ssl);
+            SSL_CTX_free(ctx);
+            closesocket(hSocket);
+            return false;
+        }
         SSL_set_fd(ssl, (int)hSocket);
 
         int ret = SSL_connect(ssl);
@@ -1944,6 +1959,15 @@ bool ThreadHTTPSeedFetch2(void* parg)
             closesocket(hSocket);
             return false;
         }
+        if (SSL_get_verify_result(ssl) != X509_V_OK) {
+            printf("HTTPS seed fetch: certificate verification failed for %s\n",
+                   seedHost.c_str());
+            SSL_shutdown(ssl);
+            SSL_free(ssl);
+            SSL_CTX_free(ctx);
+            closesocket(hSocket);
+            return false;
+        }
 
         printf("HTTPS seed fetch: TLS connection established to %s\n", seedHost.c_str());
 
@@ -1973,10 +1997,19 @@ bool ThreadHTTPSeedFetch2(void* parg)
         // Read response over TLS
         std::string response;
         char buf[4096];
+        static constexpr size_t MAX_SEED_RESPONSE_SIZE = 1024 * 1024;
         while (true) {
             int nBytes = SSL_read(ssl, buf, sizeof(buf));
             if (nBytes <= 0)
                 break;
+            if (response.size() + static_cast<size_t>(nBytes) > MAX_SEED_RESPONSE_SIZE) {
+                printf("HTTPS seed fetch: response exceeds 1 MiB limit\n");
+                SSL_shutdown(ssl);
+                SSL_free(ssl);
+                SSL_CTX_free(ctx);
+                closesocket(hSocket);
+                return false;
+            }
             response.append(buf, nBytes);
         }
 
@@ -2002,7 +2035,8 @@ bool ThreadHTTPSeedFetch2(void* parg)
 
         // Check status code
         std::string statusLine = response.substr(0, response.find("\r\n"));
-        if (statusLine.find("200") == std::string::npos) {
+        if (statusLine.size() < 12 || statusLine.compare(0, 7, "HTTP/1.") != 0 ||
+            statusLine.compare(9, 3, "200") != 0) {
             printf("HTTPS seed fetch: %s from %s\n", statusLine.c_str(), seedHost.c_str());
             return false;
         }
diff --git a/src/rpc_httpsocket.h b/src/rpc_httpsocket.h
index 20b9e67..ed38609 100644
--- a/src/rpc_httpsocket.h
+++ b/src/rpc_httpsocket.h
@@ -141,12 +141,27 @@ inline SOCKET ConnectRPCSocket(const std::string& host, int port)
     return hSocket;
 }
 
-// Create listening sockets for the RPC server. When loopbackOnly is true the
-// server binds the loopback interface(s) only; otherwise it binds the wildcard
-// address(es). IPv4 and IPv6 are bound on separate sockets (IPV6_V6ONLY) so the
-// two never conflict. Returns the bound, listening sockets; empty + strError on
-// total failure (partial success — e.g. only IPv4 — is returned as success).
-inline std::vector<SOCKET> BindRPCSockets(int port, bool loopbackOnly, std::string& strError)
+inline bool SetRPCSocketTimeouts(SOCKET socket, int timeoutSeconds)
+{
+#ifdef WIN32
+    DWORD timeout = static_cast<DWORD>(timeoutSeconds * 1000);
+#else
+    struct timeval timeout;
+    timeout.tv_sec = timeoutSeconds;
+    timeout.tv_usec = 0;
+#endif
+    const char* value = reinterpret_cast<const char*>(&timeout);
+    const socklen_t valueSize = sizeof(timeout);
+    return ::setsockopt(socket, SOL_SOCKET, SO_RCVTIMEO, value, valueSize) == 0 &&
+           ::setsockopt(socket, SOL_SOCKET, SO_SNDTIMEO, value, valueSize) == 0;
+}
+
+// Create listening sockets for the RPC server. An empty bindAddress binds only
+// localhost. A non-empty value binds exactly that address; "*" explicitly
+// requests wildcard addresses. IPv4 and IPv6 use separate sockets when the
+// selected name resolves to both families.
+inline std::vector<SOCKET> BindRPCSockets(int port, const std::string& bindAddress,
+                                           std::string& strError)
 {
     std::vector<SOCKET> vListen;
 
@@ -154,13 +169,15 @@ inline std::vector<SOCKET> BindRPCSockets(int port, bool loopbackOnly, std::stri
     std::memset(&hints, 0, sizeof(hints));
     hints.ai_family = AF_UNSPEC;
     hints.ai_socktype = SOCK_STREAM;
-    hints.ai_flags = AI_PASSIVE;  // wildcard when node == nullptr
+
+    const bool wildcard = bindAddress == "*";
+    if (wildcard)
+        hints.ai_flags = AI_PASSIVE;
 
     struct addrinfo* res = nullptr;
     const std::string portStr = std::to_string(port);
-    // "localhost" resolves to the loopback addresses (127.0.0.1 and ::1);
-    // nullptr + AI_PASSIVE yields the wildcard addresses.
-    const char* node = loopbackOnly ? "localhost" : nullptr;
+    const char* node = wildcard ? nullptr :
+        (bindAddress.empty() ? "localhost" : bindAddress.c_str());
     int gai = ::getaddrinfo(node, portStr.c_str(), &hints, &res);
     if (gai != 0) {
         strError = std::string("RPC bind: getaddrinfo failed: ") + gai_strerror(gai);
diff --git a/src/rpcblockchain.cpp b/src/rpcblockchain.cpp
index fc07be9..5a5c942 100644
--- a/src/rpcblockchain.cpp
+++ b/src/rpcblockchain.cpp
@@ -1323,91 +1323,3 @@ Value dumputxoset(const Array& params, bool fHelp)
 
     return result;
 }
-
-// ============================================================================
-// Trusted snapshot publisher RPCs (Design A: single-slot rotation)
-// ============================================================================
-//
-// settrustedv2snapshotpublisher <address>
-//   - Atomically replaces the active trusted snapshot publisher.
-//   - The previous publisher is dropped immediately (no grace period).
-//   - The new publisher is persisted to <datadir>/snapshot-publisher.json
-//     so the choice survives daemon restarts.
-//
-// gettrustedv2snapshotpublisher
-//   - Returns the currently active runtime override.
-//   - Empty string means no runtime override; built-in fallback list is
-//     the source of truth (which contains "TG8f76ykt...").
-//
-// unsettrustedv2snapshotpublisher
-//   - Clears the runtime override.
-//   - The built-in fallback list (read-only, compiled in) becomes the
-//     source of truth again.
-//   - Removes <datadir>/snapshot-publisher.json.
-Value settrustedv2snapshotpublisher(const Array& params, bool fHelp)
-{
-    if (fHelp || params.size() != 1)
-        throw runtime_error(
-            "settrustedv2snapshotpublisher <address>\n"
-            "Atomically replace the trusted snapshot publisher.\n"
-            "The previous publisher is dropped immediately (no grace period).\n"
-            "The new publisher is persisted to <datadir>/snapshot-publisher.json.\n"
-            "\nArguments:\n"
-            "1. address   (string, required)   Triangles T-address (34 chars, starts with 'T')\n"
-            "\nResult:\n"
-            "{ previous: 'T...', current: 'T...' }  (previous is empty if first set)\n"
-            "\nExample:\n"
-            "  triangles-cli settrustedv2snapshotpublisher TGotWuftzH7rD9tXC7whE8EXiyC3mr1CrH");
-
-    std::string addr = params[0].get_str();
-    std::string previous = Bootstrap::GetActiveTrustedSnapshotPublisher();
-    std::string err;
-    if (!Bootstrap::SetTrustedSnapshotPublisher(addr, err)) {
-        throw JSONRPCError(RPC_INVALID_PARAMETER, err);
-    }
-    Object result;
-    result.push_back(Pair("previous", previous));
-    result.push_back(Pair("current", addr));
-    if (!err.empty())
-        result.push_back(Pair("warning", err));
-    return result;
-}
-
-Value gettrustedv2snapshotpublisher(const Array& params, bool fHelp)
-{
-    if (fHelp || params.size() != 0)
-        throw runtime_error(
-            "gettrustedv2snapshotpublisher\n"
-            "Returns the currently active trusted snapshot publisher.\n"
-            "Empty string means no runtime override is set; the built-in\n"
-            "fallback list (compiled in) is the source of truth.\n"
-            "\nResult:\n"
-            "{ active: 'T...', has_runtime_override: true|false }");
-
-    std::string active = Bootstrap::GetActiveTrustedSnapshotPublisher();
-    Object result;
-    result.push_back(Pair("active", active));
-    result.push_back(Pair("has_runtime_override", !active.empty()));
-    return result;
-}
-
-Value unsettrustedv2snapshotpublisher(const Array& params, bool fHelp)
-{
-    if (fHelp || params.size() != 0)
-        throw runtime_error(
-            "unsettrustedv2snapshotpublisher\n"
-            "Clear the runtime trusted snapshot publisher override.\n"
-            "The built-in fallback list (compiled in) becomes the source of truth again.\n"
-            "Removes <datadir>/snapshot-publisher.json.\n"
-            "\nResult:\n"
-            "{ unset: true, fallback_in_effect: true }");
-
-    std::string err;
-    if (!Bootstrap::UnsetTrustedSnapshotPublisher(err)) {
-        throw JSONRPCError(RPC_INTERNAL_ERROR, err);
-    }
-    Object result;
-    result.push_back(Pair("unset", true));
-    result.push_back(Pair("fallback_in_effect", true));
-    return result;
-}
diff --git a/src/rpcwallet.cpp b/src/rpcwallet.cpp
index 34e9ab0..126efed 100644
--- a/src/rpcwallet.cpp
+++ b/src/rpcwallet.cpp
@@ -13,6 +13,8 @@
 #include "tor/onion_v3.h"
 #include "tor/tor_embedded.h"
 
+#include <memory>
+
 using namespace json_spirit;
 using namespace std;
 
@@ -1519,7 +1521,7 @@ Value walletpassphrase(const Array& params, bool fHelp)
     if (pwalletMain->IsCrypted() && (fHelp || params.size() < 2 || params.size() > 3))
         throw runtime_error(
             "walletpassphrase <passphrase> <timeout> [stakingonly]\n"
-            "Stores the wallet decryption key in memory for <timeout> seconds.\n"
+            "Stores the wallet decryption key in memory for <timeout> seconds (1-604800).\n"
             "if [stakingonly] is true sending functions are disabled.");
     if (fHelp)
         return true;
@@ -1530,6 +1532,14 @@ Value walletpassphrase(const Array& params, bool fHelp)
 
     if (!pwalletMain->IsLocked())
         throw JSONRPCError(RPC_WALLET_ALREADY_UNLOCKED, "Error: Wallet is already unlocked, use walletlock first if need to change unlock settings.");
+
+    const int64_t timeoutSeconds = params[1].get_int64();
+    if (timeoutSeconds < 1 || timeoutSeconds > 7 * 24 * 60 * 60)
+        throw JSONRPCError(RPC_INVALID_PARAMETER,
+                           "Wallet unlock timeout must be between 1 and 604800 seconds.");
+    const bool stakingOnly = params.size() > 2 ? params[2].get_bool() : false;
+    std::unique_ptr<int64_t> sleepTime(new int64_t(timeoutSeconds));
+
     // Note that the walletpassphrase is stored in params[0] which is not mlock()ed
     SecureString strWalletPass;
     strWalletPass.reserve(100);
@@ -1545,15 +1555,18 @@ Value walletpassphrase(const Array& params, bool fHelp)
             "walletpassphrase <passphrase> <timeout>\n"
             "Stores the wallet decryption key in memory for <timeout> seconds.");
 
-    NewThread(ThreadTopUpKeyPool, nullptr);
-    int64_t* pnSleepTime = new int64_t(params[1].get_int64());
-    NewThread(ThreadCleanWalletPassphrase, pnSleepTime);
-
     // triangles: if user OS account compromised prevent trivial sendmoney commands
-    if (params.size() > 2)
-        fWalletUnlockStakingOnly = params[2].get_bool();
-    else
+    fWalletUnlockStakingOnly = stakingOnly;
+    if (!NewThread(ThreadCleanWalletPassphrase, sleepTime.get())) {
+        pwalletMain->Lock();
         fWalletUnlockStakingOnly = false;
+        throw JSONRPCError(RPC_WALLET_ERROR,
+                           "Could not start the wallet relock timer; wallet was locked again.");
+    }
+    sleepTime.release();
+
+    if (!NewThread(ThreadTopUpKeyPool, nullptr))
+        printf("walletpassphrase: could not start background keypool refill\n");
 
     return Value::null;
 }
diff --git a/src/scrypt-arm.S b/src/scrypt-arm.S
index 143eb3a..3e4af7f 100644
--- a/src/scrypt-arm.S
+++ b/src/scrypt-arm.S
@@ -553,3 +553,8 @@ scrypt_core_loop2:
 #endif
 
 #endif
+
+
+#if defined(__ELF__)
+	.section .note.GNU-stack,"",%progbits
+#endif
diff --git a/src/scrypt-x86.S b/src/scrypt-x86.S
index c1d2cef..9c8c25c 100644
--- a/src/scrypt-x86.S
+++ b/src/scrypt-x86.S
@@ -910,3 +910,7 @@ xmm_scrypt_core_loop2:
 	ret
 
 #endif
+
+#if defined(__ELF__)
+	.section .note.GNU-stack,"",@progbits
+#endif
diff --git a/src/scrypt-x86_64.S b/src/scrypt-x86_64.S
index 7f22e40..e53654e 100644
--- a/src/scrypt-x86_64.S
+++ b/src/scrypt-x86_64.S
@@ -856,4 +856,8 @@ xmm_scrypt_core_loop2:
 	popq	%rbx
 	ret
 
-#endif
\ No newline at end of file
+#endif
+
+#if defined(__ELF__)
+	.section .note.GNU-stack,"",@progbits
+#endif
diff --git a/src/smessage.cpp b/src/smessage.cpp
index 9aa5a77..d5acdea 100644
--- a/src/smessage.cpp
+++ b/src/smessage.cpp
@@ -3555,6 +3555,8 @@ int SecureMsgValidate(unsigned char *pHeader, unsigned char *pPayload, uint32_t
         memcpy(civ+i, &nonse, 4);
     
     HMAC_CTX *ctx = HMAC_CTX_new();
+    if (ctx == nullptr)
+        return 1;
 
     unsigned int nBytes;
     if (!HMAC_Init_ex(ctx, &civ[0], 32, EVP_sha256(), nullptr)
@@ -3571,7 +3573,7 @@ int SecureMsgValidate(unsigned char *pHeader, unsigned char *pPayload, uint32_t
     {
         if (sha256Hash[31] == 0
             && sha256Hash[30] == 0
-            && (~(sha256Hash[29]) & ((1<<0) || (1<<1) || (1<<2)) ))
+            && (sha256Hash[29] & 1U) == 0)
         {
             if (fDebugSmsg)
                 printf("Hash Valid.\n");
@@ -3614,6 +3616,8 @@ int SecureMsgSetHash(unsigned char *pHeader, unsigned char *pPayload, uint32_t n
     
     bool found = false;
     HMAC_CTX *ctx = HMAC_CTX_new();
+    if (ctx == nullptr)
+        return 1;
 
     uint32_t nonse = 0;
 
@@ -3655,7 +3659,7 @@ int SecureMsgSetHash(unsigned char *pHeader, unsigned char *pPayload, uint32_t n
         
         if (sha256Hash[31] == 0
             && sha256Hash[30] == 0
-            && (~(sha256Hash[29]) & ((1<<0) || (1<<1) || (1<<2)) ))
+            && (sha256Hash[29] & 1U) == 0)
         //    && sha256Hash[29] == 0)
         {
             found = true;
@@ -3794,7 +3798,10 @@ int SecureMsgEncrypt(SecureMessage& smsg, std::string& addressFrom, std::string&
     
     // -- Generate 16 random bytes as IV.
     RandAddSeedPerfmon();
-    RAND_bytes(&smsg.iv[0], 16);
+    if (RAND_bytes(&smsg.iv[0], 16) != 1) {
+        printf("Could not generate a secure message IV.\n");
+        return 1;
+    }
     
     
     // -- Generate a new random EC key pair with private key called r and public key called R.
@@ -3959,14 +3966,16 @@ int SecureMsgEncrypt(SecureMessage& smsg, std::string& addressFrom, std::string&
     unsigned int nBytes = 32;
     HMAC_CTX *ctx = HMAC_CTX_new();
 
-    if (!HMAC_Init_ex(ctx, &key_m[0], 32, EVP_sha256(), nullptr)
+    if (ctx == nullptr
+        || !HMAC_Init_ex(ctx, &key_m[0], 32, EVP_sha256(), nullptr)
         || !HMAC_Update(ctx, (unsigned char*) &smsg.timestamp, sizeof(smsg.timestamp))
         || !HMAC_Update(ctx, &vchCiphertext[0], vchCiphertext.size())
         || !HMAC_Final(ctx, smsg.mac, &nBytes)
         || nBytes != 32)
         fHmacOk = false;
 
-    HMAC_CTX_free(ctx);
+    if (ctx != nullptr)
+        HMAC_CTX_free(ctx);
     
     if (!fHmacOk)
     {
@@ -4269,14 +4278,16 @@ int SecureMsgDecrypt(bool fTestOnly, std::string& address, unsigned char *pHeade
     unsigned int nBytes = 32;
     HMAC_CTX *ctx = HMAC_CTX_new();
 
-    if (!HMAC_Init_ex(ctx, &key_m[0], 32, EVP_sha256(), nullptr)
+    if (ctx == nullptr
+        || !HMAC_Init_ex(ctx, &key_m[0], 32, EVP_sha256(), nullptr)
         || !HMAC_Update(ctx, (unsigned char*) &psmsg->timestamp, sizeof(psmsg->timestamp))
         || !HMAC_Update(ctx, pPayload, nPayload)
         || !HMAC_Final(ctx, MAC, &nBytes)
         || nBytes != 32)
         fHmacOk = false;
 
-    HMAC_CTX_free(ctx);
+    if (ctx != nullptr)
+        HMAC_CTX_free(ctx);
     
     if (!fHmacOk)
     {
@@ -4430,4 +4441,3 @@ int SecureMsgDecrypt(bool fTestOnly, std::string& address, SecureMessage& smsg,
 {
     return SecureMsgDecrypt(fTestOnly, address, &smsg.hash[0], smsg.pPayload, smsg.nPayload, msg);
 };
-
diff --git a/src/snapshotnet.cpp b/src/snapshotnet.cpp
index 369da2f..9b08976 100644
--- a/src/snapshotnet.cpp
+++ b/src/snapshotnet.cpp
@@ -120,26 +120,18 @@ static bool VerifyDestFileHash(std::string& strErr)
         return false;
     }
     fflush(g_fetch.fpDest);
-    fseek(g_fetch.fpDest, 0, SEEK_SET);
 
-    SHA256_CTX ctx;
-    SHA256_Init(&ctx);
-
-    std::vector<unsigned char> buf(64 * 1024);
-    int64_t total = 0;
-    while (true) {
-        size_t n = fread(buf.data(), 1, buf.size(), g_fetch.fpDest);
-        if (n == 0) break;
-        SHA256_Update(&ctx, buf.data(), n);
-        total += (int64_t)n;
-    }
-    if (total != g_fetch.totalSize) {
-        strErr = strprintf("size mismatch: have %" PRId64 " want %" PRId64, total, g_fetch.totalSize);
+    std::error_code ec;
+    const int64_t total = static_cast<int64_t>(fs::file_size(g_fetch.destPath, ec));
+    if (ec || total != g_fetch.totalSize) {
+        strErr = strprintf("size mismatch: have %" PRId64 " want %" PRId64,
+                           ec ? -1 : total, g_fetch.totalSize);
         return false;
     }
 
     uint256 actual;
-    SHA256_Final((unsigned char*)&actual, &ctx);
+    if (!ComputeSnapshotFileHash(g_fetch.destPath, actual, strErr))
+        return false;
     if (actual != g_fetch.expectedFileHash) {
         strErr = "snapshot file hash mismatch";
         return false;
@@ -243,6 +235,46 @@ static void ReissueStalledChunks(int64_t timeoutMicros)
 
 } // namespace
 
+bool ComputeSnapshotFileHash(const fs::path& path,
+                             uint256& fileHash,
+                             std::string& strError)
+{
+    FILE* file = fopen(path.string().c_str(), "rb");
+    if (!file) {
+        strError = "cannot open snapshot for hashing: " + path.string();
+        return false;
+    }
+
+    SHA256_CTX ctx;
+    SHA256_Init(&ctx);
+    std::vector<unsigned char> buffer(64 * 1024);
+    while (true) {
+        const size_t count = fread(buffer.data(), 1, buffer.size(), file);
+        if (count > 0)
+            SHA256_Update(&ctx, buffer.data(), count);
+        if (count < buffer.size()) {
+            if (ferror(file)) {
+                fclose(file);
+                strError = "failed reading snapshot while hashing";
+                return false;
+            }
+            break;
+        }
+    }
+    fclose(file);
+
+    unsigned char digest[SHA256_DIGEST_LENGTH];
+    SHA256_Final(digest, &ctx);
+    static const char hex[] = "0123456789abcdef";
+    std::string digestHex(SHA256_DIGEST_LENGTH * 2, '0');
+    for (size_t i = 0; i < SHA256_DIGEST_LENGTH; ++i) {
+        digestHex[2 * i] = hex[(digest[i] >> 4) & 0x0f];
+        digestHex[2 * i + 1] = hex[digest[i] & 0x0f];
+    }
+    fileHash.SetHex(digestHex);
+    return true;
+}
+
 // ---------------------------------------------------------------------------
 // Public: TryFetchSnapshot
 // ---------------------------------------------------------------------------
@@ -424,24 +456,12 @@ static bool ScanLocalSnapshot()
     int64_t sz = (int64_t)fs::file_size(g_localPath, ec);
     if (ec) return false;
 
-    // Hash the file once on first scan to confirm it matches the compiled-in
-    // snapshot hash. A node won't advertise NODE_SNAPSHOT if the local file is
-    // corrupt or for a different height.
-    FILE* f = fopen(g_localPath.string().c_str(), "rb");
-    if (!f) return false;
-
-    SHA256_CTX ctx;
-    SHA256_Init(&ctx);
-    std::vector<unsigned char> buf(64 * 1024);
-    while (true) {
-        size_t n = fread(buf.data(), 1, buf.size(), f);
-        if (n == 0) break;
-        SHA256_Update(&ctx, buf.data(), n);
-    }
-    fclose(f);
-
     uint256 actual;
-    SHA256_Final((unsigned char*)&actual, &ctx);
+    std::string hashError;
+    if (!ComputeSnapshotFileHash(g_localPath, actual, hashError)) {
+        printf("SnapshotNet: cannot hash local snapshot: %s\n", hashError.c_str());
+        return false;
+    }
     if (actual != expectedHash) {
         printf("SnapshotNet: local utxo-snapshot.bin hash mismatch — not advertising\n");
         return false;
diff --git a/src/snapshotnet.h b/src/snapshotnet.h
index ba9ebe3..7668dd5 100644
--- a/src/snapshotnet.h
+++ b/src/snapshotnet.h
@@ -51,6 +51,12 @@ bool TryFetchSnapshot(const std::filesystem::path& dataDir,
                       int timeoutSec,
                       std::string& strError);
 
+// Return SHA256 in conventional display byte order, matching sha256sum and
+// the hexadecimal values compiled into checkpoints.cpp.
+bool ComputeSnapshotFileHash(const std::filesystem::path& path,
+                             uint256& fileHash,
+                             std::string& strError);
+
 // Server-side message dispatch. Called from main.cpp ProcessMessage.
 // Returns true if strCommand was a snapshot-protocol message (handled or
 // rejected for malformed input).
diff --git a/src/sync.h b/src/sync.h
index 7a960c1..3de6062 100644
--- a/src/sync.h
+++ b/src/sync.h
@@ -65,8 +65,7 @@ public:
         if (!lock.owns_lock())
         {
             EnterCritical(pszName, pszFile, nLine, (void*)(lock.mutex()), true);
-            lock.try_lock();
-            if (!lock.owns_lock())
+            if (!lock.try_lock())
                 LeaveCritical();
         }
         return lock.owns_lock();
@@ -204,4 +203,3 @@ public:
     }
 };
 #endif
-
diff --git a/src/test/bignum_tests.cpp b/src/test/bignum_tests.cpp
index b161f2c..2064853 100644
--- a/src/test/bignum_tests.cpp
+++ b/src/test/bignum_tests.cpp
@@ -1,125 +1,74 @@
 #include <boost/test/unit_test.hpp>
 #include <limits>
+#include <string>
 
 #include "bignum.h"
 #include "util.h"
 
 BOOST_AUTO_TEST_SUITE(bignum_tests)
 
-// Unfortunately there's no standard way of preventing a function from being
-// inlined, so we define a macro for it.
-//
-// You should use it like this:
-//   NOINLINE void function() {...}
 #if defined(__GNUC__)
-// This also works and will be defined for any compiler implementing GCC
-// extensions, such as Clang and ICC.
 #define NOINLINE __attribute__((noinline))
 #elif defined(_MSC_VER)
 #define NOINLINE __declspec(noinline)
 #else
-// We give out a warning because it impacts the correctness of one bignum test.
-#warning You should define NOINLINE for your compiler.
 #define NOINLINE
 #endif
 
-// For the following test case, it is useful to use additional tools.
-//
-// The simplest one to use is the compiler flag -ftrapv, which detects integer
-// overflows and similar errors. However, due to optimizations and compilers
-// taking advantage of undefined behavior sometimes it may not actually detect
-// anything.
-//
-// You can also use compiler-based stack protection to possibly detect possible
-// stack buffer overruns.
-//
-// For more accurate diagnostics, you can use an undefined arithmetic operation
-// detector such as the clang-based tool:
-//
-// "IOC: An Integer Overflow Checker for C/C++"
-//
-// Available at: http://embed.cs.utah.edu/ioc/
-//
-// It might also be useful to use Google's AddressSanitizer to detect
-// stack buffer overruns, which valgrind can't currently detect.
-
-// Let's force this code not to be inlined, in order to actually
-// test a generic version of the function. This increases the chance
-// that -ftrapv will detect overflows.
 NOINLINE void mysetint64(CBigNum& num, int64_t n)
 {
     num.setint64(n);
 }
 
-// For each number, we do 2 tests: one with inline code, then we reset the
-// value to 0, then the second one with a non-inlined function.
 BOOST_AUTO_TEST_CASE(bignum_setint64)
 {
-    int64_t n;
+    const int64_t values[] = {
+        0,
+        1,
+        -1,
+        5,
+        -5,
+        std::numeric_limits<int64_t>::min(),
+        std::numeric_limits<int64_t>::max(),
+    };
 
-    {
-        n = 0;
-        CBigNum num(n);
-        BOOST_CHECK(num.ToString() == "0");
+    for (int64_t value : values) {
+        CBigNum num(value);
+        BOOST_CHECK_EQUAL(num.ToString(), std::to_string(value));
         num.setulong(0);
-        BOOST_CHECK(num.ToString() == "0");
-        mysetint64(num, n);
-        BOOST_CHECK(num.ToString() == "0");
-    }
-    {
-        n = 1;
-        CBigNum num(n);
-        BOOST_CHECK(num.ToString() == "1");
-        num.setulong(0);
-        BOOST_CHECK(num.ToString() == "0");
-        mysetint64(num, n);
-        BOOST_CHECK(num.ToString() == "1");
-    }
-    {
-        n = -1;
-        CBigNum num(n);
-        BOOST_CHECK(num.ToString() == "-1");
-        num.setulong(0);
-        BOOST_CHECK(num.ToString() == "0");
-        mysetint64(num, n);
-        BOOST_CHECK(num.ToString() == "-1");
-    }
-    {
-        n = 5;
-        CBigNum num(n);
-        BOOST_CHECK(num.ToString() == "5");
-        num.setulong(0);
-        BOOST_CHECK(num.ToString() == "0");
-        mysetint64(num, n);
-        BOOST_CHECK(num.ToString() == "5");
-    }
-    {
-        n = -5;
-        CBigNum num(n);
-        BOOST_CHECK(num.ToString() == "-5");
-        num.setulong(0);
-        BOOST_CHECK(num.ToString() == "0");
-        mysetint64(num, n);
-        BOOST_CHECK(num.ToString() == "-5");
-    }
-    {
-        n = std::numeric_limits<int64_t>::min();
-        CBigNum num(n);
-        BOOST_CHECK(num.ToString() == "-9223372036854775808");
-        num.setulong(0);
-        BOOST_CHECK(num.ToString() == "0");
-        mysetint64(num, n);
-        BOOST_CHECK(num.ToString() == "-9223372036854775808");
-    }
-    {
-        n = std::numeric_limits<int64_t>::max();
-        CBigNum num(n);
-        BOOST_CHECK(num.ToString() == "9223372036854775807");
-        num.setulong(0);
-        BOOST_CHECK(num.ToString() == "0");
-        mysetint64(num, n);
-        BOOST_CHECK(num.ToString() == "9223372036854775807");
+        BOOST_CHECK_EQUAL(num.ToString(), "0");
+        mysetint64(num, value);
+        BOOST_CHECK_EQUAL(num.ToString(), std::to_string(value));
     }
 }
 
+BOOST_AUTO_TEST_CASE(bignum_uint64_roundtrip_boundaries)
+{
+    const uint64_t values[] = {
+        0,
+        1,
+        0x7f,
+        0x80,
+        uint64_t{1} << 32,
+        uint64_t{1} << 63,
+        std::numeric_limits<uint64_t>::max(),
+    };
+
+    for (uint64_t value : values) {
+        CBigNum num(value);
+        BOOST_CHECK_EQUAL(num.getuint64(), value);
+    }
+
+    CBigNum negative(-1);
+    BOOST_CHECK_EQUAL(negative.getuint64(), uint64_t{1});
+}
+
+BOOST_AUTO_TEST_CASE(bignum_rejects_invalid_output_base)
+{
+    CBigNum value(42);
+    BOOST_CHECK_THROW(value.ToString(0), bignum_error);
+    BOOST_CHECK_THROW(value.ToString(1), bignum_error);
+    BOOST_CHECK_THROW(value.ToString(17), bignum_error);
+}
+
 BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/test/bootstrap_security_tests.cpp b/src/test/bootstrap_security_tests.cpp
new file mode 100644
index 0000000..7e27d12
--- /dev/null
+++ b/src/test/bootstrap_security_tests.cpp
@@ -0,0 +1,79 @@
+// Copyright (c) 2026 Triangles developers
+// Distributed under the MIT/X11 software license
+
+#include <boost/test/unit_test.hpp>
+
+#include "../bootstrap.h"
+
+namespace {
+
+std::string ManifestWithFilename(const std::string& filename)
+{
+    return std::string(R"json({
+        "version": "1.6",
+        "chain_tip": {
+            "height": 2206004,
+            "blockhash": "b34e8e6a7bb7f52167d81aaad4d26f87a876898fdd0fce860916fc1aaf9a2a46"
+        },
+        "files": {
+            ")json") + filename + R"json(": {
+                "sha256": "1419282DAE817315EE1B955543F6248233FE5800F5E8488734A0ECE5BD6781EA",
+                "type": "utxo_snapshot_v3"
+            }
+        },
+        "canonical": { "snapshot": ")json" + filename + R"json(" }
+    })json";
+}
+
+} // namespace
+
+BOOST_AUTO_TEST_SUITE(bootstrap_security_tests)
+
+BOOST_AUTO_TEST_CASE(remote_manifest_parses_canonical_snapshot)
+{
+    Bootstrap::RemoteSnapshot snapshot;
+    std::string error;
+    BOOST_REQUIRE(Bootstrap::ParseRemoteSnapshotManifest(
+        ManifestWithFilename("utxo-snapshot.bin"), snapshot, error));
+    BOOST_CHECK_EQUAL(snapshot.filename, "utxo-snapshot.bin");
+    BOOST_CHECK_EQUAL(snapshot.height, 2206004);
+    BOOST_CHECK_EQUAL(
+        snapshot.sha256,
+        "1419282dae817315ee1b955543f6248233fe5800f5e8488734a0ece5bd6781ea");
+}
+
+BOOST_AUTO_TEST_CASE(remote_manifest_rejects_path_traversal)
+{
+    Bootstrap::RemoteSnapshot snapshot;
+    std::string error;
+    BOOST_CHECK(!Bootstrap::ParseRemoteSnapshotManifest(
+        ManifestWithFilename("../../wallet.dat"), snapshot, error));
+    BOOST_CHECK_NE(error.find("plain filename"), std::string::npos);
+}
+
+BOOST_AUTO_TEST_CASE(remote_manifest_rejects_malformed_hashes)
+{
+    std::string manifest = ManifestWithFilename("utxo-snapshot.bin");
+    const std::string validHash =
+        "1419282DAE817315EE1B955543F6248233FE5800F5E8488734A0ECE5BD6781EA";
+    manifest.replace(manifest.find(validHash), validHash.size(), "not-a-sha256");
+
+    Bootstrap::RemoteSnapshot snapshot;
+    std::string error;
+    BOOST_CHECK(!Bootstrap::ParseRemoteSnapshotManifest(manifest, snapshot, error));
+    BOOST_CHECK_NE(error.find("invalid"), std::string::npos);
+}
+
+BOOST_AUTO_TEST_CASE(remote_manifest_rejects_non_snapshot_canonical_file)
+{
+    std::string manifest = ManifestWithFilename("wallet.dat");
+    const std::string snapshotType = "utxo_snapshot_v3";
+    manifest.replace(manifest.find(snapshotType), snapshotType.size(), "wallet_backup");
+
+    Bootstrap::RemoteSnapshot snapshot;
+    std::string error;
+    BOOST_CHECK(!Bootstrap::ParseRemoteSnapshotManifest(manifest, snapshot, error));
+    BOOST_CHECK_NE(error.find("not a UTXO snapshot"), std::string::npos);
+}
+
+BOOST_AUTO_TEST_SUITE_END()
diff --git a/src/test/chaindb_equivalence_tests_main.cpp b/src/test/chaindb_equivalence_tests_main.cpp
index 4e1384f..1468731 100644
--- a/src/test/chaindb_equivalence_tests_main.cpp
+++ b/src/test/chaindb_equivalence_tests_main.cpp
@@ -34,6 +34,7 @@ bool fUseFastIndex = false;
 enum Checkpoints::CPMode CheckpointsMode = Checkpoints::STRICT;
 
 void StartShutdown() { /* no-op for tests */ }
+void MarkShutdownFailure() { /* no-op for tests */ }
 
 namespace {
 
diff --git a/src/test/chaindb_runtime_tests.cpp b/src/test/chaindb_runtime_tests.cpp
index d4f45aa..53a0655 100644
--- a/src/test/chaindb_runtime_tests.cpp
+++ b/src/test/chaindb_runtime_tests.cpp
@@ -125,6 +125,7 @@ bool fUseFastIndex = false;
 enum Checkpoints::CPMode CheckpointsMode = Checkpoints::STRICT;
 
 void StartShutdown() { /* no-op */ }
+void MarkShutdownFailure() { /* no-op for tests */ }
 
 namespace {
 
diff --git a/src/test/consensus_safety_tests.cpp b/src/test/consensus_safety_tests.cpp
index d531194..06497ea 100644
--- a/src/test/consensus_safety_tests.cpp
+++ b/src/test/consensus_safety_tests.cpp
@@ -358,6 +358,23 @@ BOOST_AUTO_TEST_CASE(pos_validation_skip_is_only_historical_fast_path)
     nAssumeValidThreshold = oldAssumeValid;
 }
 
+BOOST_AUTO_TEST_CASE(pos_block_signature_is_required_above_hardened_checkpoint)
+{
+    const int oldAssumeValid = nAssumeValidThreshold;
+    const int checkpointHeight = Checkpoints::GetTotalBlocksEstimate();
+
+    BOOST_CHECK(!IsBlockSignatureRequiredAtHeight(checkpointHeight));
+    BOOST_CHECK(IsBlockSignatureRequiredAtHeight(checkpointHeight + 1));
+
+    // A rolling performance threshold must never authorize unsigned live
+    // blocks, including when stale-tip state makes the node report IBD.
+    nAssumeValidThreshold = checkpointHeight + 100;
+    BOOST_CHECK(IsConsensusAssumeValidHeight(checkpointHeight + 50));
+    BOOST_CHECK(IsBlockSignatureRequiredAtHeight(checkpointHeight + 50));
+
+    nAssumeValidThreshold = oldAssumeValid;
+}
+
 // ─── Orphan block cap (P1 — DoS) ──────────────────────────────────────────
 // The cap on stored orphan blocks prevents an attacker from filling
 // memory with garbage. If too low, legitimate orphans are dropped. If
diff --git a/src/test/snapshotnet_tests.cpp b/src/test/snapshotnet_tests.cpp
index b89bd18..d5cfad7 100644
--- a/src/test/snapshotnet_tests.cpp
+++ b/src/test/snapshotnet_tests.cpp
@@ -70,6 +70,7 @@ bool fUseFastIndex = false;
 enum Checkpoints::CPMode CheckpointsMode = Checkpoints::STRICT;
 
 void StartShutdown() { /* no-op for tests */ }
+void MarkShutdownFailure() { /* no-op for tests */ }
 
 namespace {
 
@@ -100,19 +101,9 @@ struct TmpDataDir
 // Compute SHA-256 of a file's bytes.
 uint256 Sha256OfFile(const fs::path& p)
 {
-    FILE* f = fopen(p.string().c_str(), "rb");
-    BOOST_REQUIRE_MESSAGE(f != nullptr, "open failed: " << p.string());
-    SHA256_CTX ctx;
-    SHA256_Init(&ctx);
-    std::vector<unsigned char> buf(64 * 1024);
-    while (true) {
-        size_t n = fread(buf.data(), 1, buf.size(), f);
-        if (n == 0) break;
-        SHA256_Update(&ctx, buf.data(), n);
-    }
-    fclose(f);
     uint256 out;
-    SHA256_Final(reinterpret_cast<unsigned char*>(&out), &ctx);
+    std::string error;
+    BOOST_REQUIRE_MESSAGE(SnapshotNet::ComputeSnapshotFileHash(p, out, error), error);
     return out;
 }
 
@@ -121,8 +112,16 @@ uint256 Sha256OfBytes(const std::vector<unsigned char>& bytes)
     SHA256_CTX ctx;
     SHA256_Init(&ctx);
     SHA256_Update(&ctx, bytes.data(), bytes.size());
+    unsigned char digest[SHA256_DIGEST_LENGTH];
+    SHA256_Final(digest, &ctx);
+    static const char hex[] = "0123456789abcdef";
+    std::string digestHex(SHA256_DIGEST_LENGTH * 2, '0');
+    for (size_t i = 0; i < SHA256_DIGEST_LENGTH; ++i) {
+        digestHex[2 * i] = hex[(digest[i] >> 4) & 0x0f];
+        digestHex[2 * i + 1] = hex[digest[i] & 0x0f];
+    }
     uint256 out;
-    SHA256_Final(reinterpret_cast<unsigned char*>(&out), &ctx);
+    out.SetHex(digestHex);
     return out;
 }
 
@@ -177,6 +176,17 @@ BOOST_AUTO_TEST_SUITE_END()
 
 BOOST_AUTO_TEST_SUITE(snapshotnet_hash)
 
+BOOST_AUTO_TEST_CASE(file_hash_uses_standard_sha256_display_order)
+{
+    TmpDataDir td;
+    fs::path p = td.path / "abc.bin";
+    WriteFile(p, {'a', 'b', 'c'});
+
+    BOOST_CHECK_EQUAL(
+        Sha256OfFile(p).ToString(),
+        "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad");
+}
+
 BOOST_AUTO_TEST_CASE(file_hash_matches_inline_sha256)
 {
     // Synthesize a payload, hash it via stdlib openssl directly, then hash
diff --git a/src/test/test_triangles.cpp b/src/test/test_triangles.cpp
index 3090d93..17f0fb8 100644
--- a/src/test/test_triangles.cpp
+++ b/src/test/test_triangles.cpp
@@ -69,3 +69,4 @@ void StartShutdown()
   exit(0);
 }
 
+void MarkShutdownFailure() { /* no-op for tests */ }
diff --git a/src/test/util_tests.cpp b/src/test/util_tests.cpp
index a8db143..757a0dc 100644
--- a/src/test/util_tests.cpp
+++ b/src/test/util_tests.cpp
@@ -168,6 +168,15 @@ BOOST_AUTO_TEST_CASE(util_WildcardMatch)
     BOOST_CHECK(WildcardMatch("abcdef", "a*f"));
     BOOST_CHECK(!WildcardMatch("abcdef", "a*x"));
     BOOST_CHECK(WildcardMatch("", "*"));
+
+    const std::string address = "192.0.2.44";
+    const std::string allow = "192.0.2.*";
+    BOOST_CHECK(WildcardMatch(std::string_view(address), std::string_view(allow)));
+
+    // A long non-match must not recurse once per wildcard/input combination.
+    const std::string longInput(4096, 'a');
+    const std::string longMask = "*a*a*a*a*a*a*a*a*a*a*b";
+    BOOST_CHECK(!WildcardMatch(std::string_view(longInput), std::string_view(longMask)));
 }
 
 BOOST_AUTO_TEST_CASE(util_FormatMoney)
diff --git a/src/test/wallet_tests.cpp b/src/test/wallet_tests.cpp
index bb477b8..25e63e6 100644
--- a/src/test/wallet_tests.cpp
+++ b/src/test/wallet_tests.cpp
@@ -294,6 +294,57 @@ BOOST_AUTO_TEST_CASE(coin_selection_tests)
 
 BOOST_AUTO_TEST_SUITE_END()
 
+BOOST_AUTO_TEST_SUITE(wallet_security_tests)
+
+BOOST_AUTO_TEST_CASE(hd_key_generation_fails_when_seed_is_unavailable)
+{
+    CWallet wallet;
+    wallet.fHDEnabled = true;
+
+    BOOST_CHECK_THROW(wallet.GenerateNewKey(), std::runtime_error);
+    BOOST_CHECK_EQUAL(wallet.nHDChainIndex, 0);
+}
+
+BOOST_AUTO_TEST_CASE(memory_wallet_encryption_roundtrip_preserves_keys)
+{
+    CWallet wallet;
+    CKey original;
+    original.MakeNewKey(true);
+    BOOST_REQUIRE(wallet.AddKey(original));
+
+    SecureString passphrase;
+    passphrase.reserve(100);
+    passphrase = "correct horse battery staple";
+
+    const auto keypoolIt = mapArgs.find("-keypool");
+    const bool hadKeypoolArg = keypoolIt != mapArgs.end();
+    const std::string oldKeypoolArg = hadKeypoolArg ? keypoolIt->second : std::string();
+    mapArgs["-keypool"] = "0";
+    const bool encrypted = wallet.EncryptWallet(passphrase);
+    if (hadKeypoolArg)
+        mapArgs["-keypool"] = oldKeypoolArg;
+    else
+        mapArgs.erase("-keypool");
+
+    BOOST_REQUIRE(encrypted);
+    BOOST_CHECK(wallet.IsCrypted());
+    BOOST_CHECK(wallet.IsLocked());
+
+    SecureString wrongPassphrase;
+    wrongPassphrase.reserve(100);
+    wrongPassphrase = "wrong passphrase";
+    BOOST_CHECK(!wallet.Unlock(wrongPassphrase));
+    BOOST_CHECK(wallet.IsLocked());
+
+    BOOST_REQUIRE(wallet.Unlock(passphrase));
+    CKey recovered;
+    BOOST_REQUIRE(wallet.GetKey(original.GetPubKey().GetID(), recovered));
+    BOOST_CHECK(recovered.GetPubKey() == original.GetPubKey());
+    BOOST_CHECK(wallet.Lock());
+}
+
+BOOST_AUTO_TEST_SUITE_END()
+
 // ----------------------------------------------------------------------------
 // AbandonTransaction tests
 //
diff --git a/src/triangles-cli.cpp b/src/triangles-cli.cpp
index 1c6fbc4..37b7c5c 100644
--- a/src/triangles-cli.cpp
+++ b/src/triangles-cli.cpp
@@ -19,7 +19,7 @@
 // Connection parameters (highest precedence first):
 //   1. Command line flags: -rpcuser/-rpcpassword/-rpcconnect/-rpcport
 //   2. triangles.conf in the data directory (or -conf=<path>)
-//   3. Defaults: 127.0.0.1:19111 mainnet, 19112 testnet; no auth (must be set in conf)
+//   3. Defaults: 127.0.0.1:19112 mainnet, 19111 testnet; no auth (must be set in conf)
 //
 // Usage:
 //   triangles-cli help                              List commands (delegates to daemon)
@@ -70,6 +70,7 @@
   #define TRI_CLI_CLOSE_SOCKET(s) closesocket(s)
 #else
   #include <sys/types.h>
+  #include <sys/stat.h>
   #include <sys/socket.h>
   #include <netinet/in.h>
   #include <arpa/inet.h>
@@ -108,10 +109,20 @@ static bool GetBoolArg(const string& key, bool def)
     return (v != "0" && v != "false" && v != "no");
 }
 
-static void ReadConfigFile(const string& path)
+static bool ReadConfigFile(const string& path, string& error)
 {
+#ifndef _WIN32
+    struct stat configStat;
+    if (::lstat(path.c_str(), &configStat) == 0 &&
+        (!S_ISREG(configStat.st_mode) || configStat.st_uid != geteuid() ||
+         (configStat.st_mode & (S_IRWXG | S_IRWXO)) != 0)) {
+        error = "refusing insecure configuration file " + path +
+                "; require a regular file owned by the current user with no group or other access";
+        return false;
+    }
+#endif
     ifstream f(path);
-    if (!f.good()) return;
+    if (!f.good()) return true;
     string line;
     while (getline(f, line)) {
         if (!line.empty() && line.back() == '\r') line.pop_back();
@@ -141,6 +152,7 @@ static void ReadConfigFile(const string& path)
             mapMultiArgs[dashKey].push_back(value);
         }
     }
+    return true;
 }
 
 static fs::path GetDefaultDataDir()
@@ -231,7 +243,7 @@ static void ParseCommandLine(int argc, char* const argv[])
 
 struct RPCConn {
     string host = "127.0.0.1";
-    string port = "19111";
+    string port = "19112";
     string user;
     string pass;
 };
@@ -244,11 +256,17 @@ static int AppInitRPCConn(RPCConn& conn)
     {
         std::ifstream f(confPath);
         confExisted = f.good();
-        if (confExisted) ReadConfigFile(confPath.string());
+        if (confExisted) {
+            string configError;
+            if (!ReadConfigFile(confPath.string(), configError)) {
+                cerr << "triangles-cli: " << configError << "\n";
+                return 1;
+            }
+        }
     }
 
     bool fTestNet = GetBoolArg("-testnet", false);
-    conn.port = GetArg("-rpcport", fTestNet ? "19112" : "19111");
+    conn.port = GetArg("-rpcport", fTestNet ? "19111" : "19112");
     conn.host = GetArg("-rpcconnect", "127.0.0.1");
     conn.user = GetArg("-rpcuser", "");
     conn.pass = GetArg("-rpcpassword", "");
@@ -595,9 +613,9 @@ static int CommandLineHelp(ostream& out)
         << "Options:\n"
         << "  -conf=<file>       Specify configuration file (default: triangles.conf)\n"
         << "  -datadir=<dir>     Specify data directory\n"
-        << "  -testnet           Use testnet (RPC port 19112)\n"
+        << "  -testnet           Use testnet (RPC port 19111)\n"
         << "  -rpcconnect=<ip>   Send commands to node running on <ip> (default: 127.0.0.1)\n"
-        << "  -rpcport=<port>    Connect to JSON-RPC on <port> (default: 19111 or testnet: 19112)\n"
+        << "  -rpcport=<port>    Connect to JSON-RPC on <port> (default: 19112 or testnet: 19111)\n"
         << "  -rpcuser=<user>    Username for JSON-RPC connections\n"
         << "  -rpcpassword=<pw>  Password for JSON-RPC connections\n"
         << "  -stdin             Read extra params from standard input, one per line\n"
diff --git a/src/trianglesrpc.cpp b/src/trianglesrpc.cpp
index a6d313f..ad4957e 100644
--- a/src/trianglesrpc.cpp
+++ b/src/trianglesrpc.cpp
@@ -17,10 +17,12 @@
 
 #undef printf
 #include "rpc_httpsocket.h"   // raw-socket HTTP transport (replaces Boost.Asio)
-#include <filesystem>
-#include <fstream>
-#include <memory>
-#include <list>
+#include <filesystem>
+#include <fstream>
+#include <memory>
+#include <list>
+#include <cerrno>
+#include <limits>
 
 #ifndef WIN32
 #include <sys/select.h>
@@ -34,13 +36,26 @@ namespace fs = std::filesystem;
 
 void ThreadRPCServer2(void* parg);
 
-static std::string strRPCUserColonPass;
+static std::string strRPCUserColonPass;
 
 const Object emptyobj;
 
 CNotificationQueue* pNotificationQueue = nullptr;
 
-void ThreadRPCServer3(void* parg);
+void ThreadRPCServer3(void* parg);
+
+static bool RPCMethodAllowed(const std::string& method)
+{
+    const auto it = mapMultiArgs.find("-rpcallowmethod");
+    if (it == mapMultiArgs.end() || it->second.empty())
+        return true;
+
+    for (const std::string& allowed : it->second) {
+        if (allowed == method)
+            return true;
+    }
+    return false;
+}
 
 static inline unsigned short GetDefaultRPCPort()
 {
@@ -316,11 +331,8 @@ static const CRPCCommand vRPCCommands[] =
     { "sendrawtransaction",     &sendrawtransaction,     false,  false },
     { "getcheckpoint",          &getcheckpoint,          true,   false },
     { "gencheckpoints",         &gencheckpoints,          true,   false },
-    { "publishcheckpoint",      &publishcheckpoint,       true,   false },
-        { "settrustedv2snapshotpublisher",   &settrustedv2snapshotpublisher,   false,  false },
-        { "gettrustedv2snapshotpublisher",   &gettrustedv2snapshotpublisher,   false,  false },
-        { "unsettrustedv2snapshotpublisher", &unsettrustedv2snapshotpublisher, false,  false },
-        { "getchaintips",           &getchaintips,           true,   false },
+    { "publishcheckpoint",      &publishcheckpoint,       true,   false },
+    { "getchaintips",           &getchaintips,           true,   false },
     { "invalidateblock",        &invalidateblock,        false,  false },
     { "reconsiderblock",        &reconsiderblock,        false,  false },
     { "recalculatesupply",      &recalculatesupply,      false,  false },
@@ -455,11 +467,27 @@ static string HTTPReply(int nStatus, const string& strMsg, bool keepalive)
         strMsg.c_str());
 }
 
-int ReadHTTPStatus(std::basic_istream<char>& stream, int &proto,
-                   string& strMethodHTTP, string& strURI)
-{
-    string str;
-    getline(stream, str);
+static bool ReadHTTPLine(std::basic_istream<char>& stream, std::string& line,
+                         size_t maxLength)
+{
+    line.clear();
+    char c = 0;
+    while (stream.get(c)) {
+        if (c == '\n')
+            return true;
+        if (line.size() >= maxLength)
+            return false;
+        line.push_back(c);
+    }
+    return false;
+}
+
+int ReadHTTPStatus(std::basic_istream<char>& stream, int &proto,
+                   string& strMethodHTTP, string& strURI)
+{
+    string str;
+    if (!ReadHTTPLine(stream, str, 8192))
+        return HTTP_BAD_REQUEST;
     // Trim trailing \r
     if (!str.empty() && str[str.size()-1] == '\r')
         str.resize(str.size()-1);
@@ -482,27 +510,45 @@ int ReadHTTPStatus(std::basic_istream<char>& stream, int &proto,
     return atoi(vWords[1].c_str());
 }
 
-int ReadHTTPHeader(std::basic_istream<char>& stream, map<string, string>& mapHeadersRet)
-{
-    int nLen = 0;
-    while (true)
-    {
-        string str;
-        std::getline(stream, str);
-        if (str.empty() || str == "\r")
-            break;
+int ReadHTTPHeader(std::basic_istream<char>& stream, map<string, string>& mapHeadersRet)
+{
+    int nLen = 0;
+    size_t totalHeaderBytes = 0;
+    while (true)
+    {
+        string str;
+        if (!ReadHTTPLine(stream, str, 8192))
+            return -1;
+        totalHeaderBytes += str.size() + 1;
+        if (totalHeaderBytes > 64 * 1024)
+            return -1;
+        if (str.empty() || str == "\r")
+            break;
         string::size_type nColon = str.find(":");
         if (nColon != string::npos)
         {
-            string strHeader = str.substr(0, nColon);
-            strHeader = TrimString(strHeader);
-            strHeader = ToLower(strHeader);
-            string strValue = str.substr(nColon+1);
-            strValue = TrimString(strValue);
-            mapHeadersRet[strHeader] = strValue;
-            if (strHeader == "content-length")
-                nLen = atoi(strValue.c_str());
-        }
+            string strHeader = str.substr(0, nColon);
+            strHeader = TrimString(strHeader);
+            strHeader = ToLower(strHeader);
+            string strValue = str.substr(nColon+1);
+            strValue = TrimString(strValue);
+            if (strHeader == "transfer-encoding" ||
+                (strHeader == "content-length" && mapHeadersRet.count(strHeader) != 0)) {
+                return -1;
+            }
+            mapHeadersRet[strHeader] = strValue;
+            if (strHeader == "content-length") {
+                errno = 0;
+                char* end = nullptr;
+                const unsigned long long parsed = std::strtoull(strValue.c_str(), &end, 10);
+                if (errno != 0 || end == strValue.c_str() || *end != '\0' ||
+                    parsed > static_cast<unsigned long long>(MAX_SIZE) ||
+                    parsed > static_cast<unsigned long long>(std::numeric_limits<int>::max())) {
+                    return -1;
+                }
+                nLen = static_cast<int>(parsed);
+            }
+        }
     }
     return nLen;
 }
@@ -702,8 +748,16 @@ void ThreadRPCServer2(void* parg)
     if ((mapArgs["-rpcpassword"] == "") ||
         (mapArgs["-rpcuser"] == mapArgs["-rpcpassword"]))
     {
-        unsigned char rand_pwd[32];
-        RAND_bytes(rand_pwd, 32);
+        unsigned char rand_pwd[32];
+        if (RAND_bytes(rand_pwd, sizeof(rand_pwd)) != 1) {
+            uiInterface.ThreadSafeMessageBox(
+                _("Unable to generate a secure suggested RPC password. "
+                  "The RPC server will not start."),
+                _("Error"), CClientUIInterface::OK | CClientUIInterface::MODAL);
+            MarkShutdownFailure();
+            StartShutdown();
+            return;
+        }
         string strWhatAmI = "To use trianglesd";
         if (mapArgs.count("-server"))
             strWhatAmI = strprintf(_("To use the %s option"), "\"-server\"");
@@ -720,8 +774,9 @@ void ThreadRPCServer2(void* parg)
                 strWhatAmI.c_str(),
                 GetConfigFile().string().c_str(),
                 EncodeBase58(&rand_pwd[0],&rand_pwd[0]+32).c_str()),
-            _("Error"), CClientUIInterface::OK | CClientUIInterface::MODAL);
-        StartShutdown();
+            _("Error"), CClientUIInterface::OK | CClientUIInterface::MODAL);
+        MarkShutdownFailure();
+        StartShutdown();
         return;
     }
 
@@ -732,23 +787,23 @@ void ThreadRPCServer2(void* parg)
                "or Tor.\n");
     }
 
-    // Bind the loopback interface(s) unless the operator explicitly opened the
-    // RPC port to other hosts with -rpcallowip.
-    const bool loopbackOnly = !mapArgs.count("-rpcallowip");
-    const int nPort = (int)GetArg("-rpcport", GetDefaultRPCPort());
-
-    std::string strBindError;
-    std::vector<SOCKET> vListen = BindRPCSockets(nPort, loopbackOnly, strBindError);
+    const int nPort = (int)GetArg("-rpcport", GetDefaultRPCPort());
+    const std::string rpcBind = GetArg(
+        std::string_view{"-rpcbind"}, std::string_view{""});
+
+    std::string strBindError;
+    std::vector<SOCKET> vListen = BindRPCSockets(nPort, rpcBind, strBindError);
     if (vListen.empty()) {
         uiInterface.ThreadSafeMessageBox(
-            strprintf(_("An error occurred while setting up the RPC port %d for listening: %s"),
-                      nPort, strBindError.c_str()),
-            _("Error"), CClientUIInterface::OK | CClientUIInterface::MODAL);
-        StartShutdown();
+            strprintf(_("An error occurred while setting up the RPC port %d for listening: %s"),
+                      nPort, strBindError.c_str()),
+            _("Error"), CClientUIInterface::OK | CClientUIInterface::MODAL);
+        MarkShutdownFailure();
+        StartShutdown();
         return;
     }
-    printf("RPC server listening on port %d (%s)\n", nPort,
-           loopbackOnly ? "loopback only" : "all interfaces");
+    printf("RPC server listening on port %d (%s)\n", nPort,
+           rpcBind.empty() ? "loopback only" : rpcBind.c_str());
 
     // Accept loop. select() with a short timeout keeps the listener responsive
     // to fShutdown. Each accepted connection is handed to its own handler thread
@@ -780,10 +835,19 @@ void ThreadRPCServer2(void* parg)
             struct sockaddr_storage ss;
             socklen_t len = sizeof(ss);
             SOCKET hConn = accept(s, (struct sockaddr*)&ss, &len);
-            if (hConn == INVALID_SOCKET) {
-                printf("RPC accept() failed\n");
-                continue;
-            }
+            if (hConn == INVALID_SOCKET) {
+                printf("RPC accept() failed\n");
+                continue;
+            }
+
+            int64_t timeoutSeconds = GetArg("-rpcservertimeout", 30);
+            if (timeoutSeconds < 1)
+                timeoutSeconds = 1;
+            if (timeoutSeconds > 600)
+                timeoutSeconds = 600;
+            if (!SetRPCSocketTimeouts(hConn, static_cast<int>(timeoutSeconds))) {
+                printf("RPC warning: failed to set connection timeouts\n");
+            }
 
             const std::string strPeer = SockaddrToString((struct sockaddr*)&ss, len);
 
@@ -979,7 +1043,13 @@ void ThreadRPCServer3(void* parg)
         map<string, string> mapHeaders;
         string strRequest;
 
-        ReadHTTP(conn->stream(), mapHeaders, strRequest);
+        const int requestStatus = ReadHTTP(conn->stream(), mapHeaders, strRequest);
+        if (requestStatus != 0) {
+            conn->stream() << HTTPReply(HTTP_BAD_REQUEST,
+                                        "{\"error\":\"Malformed HTTP request\"}",
+                                        false) << std::flush;
+            break;
+        }
 
         // Handle REST API requests
         string strHTTPMethod = mapHeaders.count("_method") ? mapHeaders["_method"] : "POST";
@@ -1097,9 +1167,12 @@ void ThreadRPCServer3(void* parg)
     }
 }
 
-json_spirit::Value CRPCTable::execute(const std::string &strMethod, const json_spirit::Array &params) const
-{
-    // Find method
+json_spirit::Value CRPCTable::execute(const std::string &strMethod, const json_spirit::Array &params) const
+{
+    if (!RPCMethodAllowed(strMethod))
+        throw JSONRPCError(RPC_METHOD_NOT_FOUND, "Method not found");
+
+    // Find method
     const CRPCCommand *pcmd = tableRPC[strMethod];
     if (!pcmd)
         throw JSONRPCError(RPC_METHOD_NOT_FOUND, "Method not found");
diff --git a/src/trianglesrpc.h b/src/trianglesrpc.h
index 8488adf..9dcf085 100644
--- a/src/trianglesrpc.h
+++ b/src/trianglesrpc.h
@@ -228,9 +228,6 @@ extern json_spirit::Value getblockbynumber(const json_spirit::Array& params, boo
 extern json_spirit::Value getcheckpoint(const json_spirit::Array& params, bool fHelp);
 extern json_spirit::Value gencheckpoints(const json_spirit::Array& params, bool fHelp);
 extern json_spirit::Value publishcheckpoint(const json_spirit::Array& params, bool fHelp);
-extern json_spirit::Value settrustedv2snapshotpublisher(const json_spirit::Array& params, bool fHelp);
-extern json_spirit::Value gettrustedv2snapshotpublisher(const json_spirit::Array& params, bool fHelp);
-extern json_spirit::Value unsettrustedv2snapshotpublisher(const json_spirit::Array& params, bool fHelp);
 extern json_spirit::Value getchaintips(const json_spirit::Array& params, bool fHelp);
 extern json_spirit::Value invalidateblock(const json_spirit::Array& params, bool fHelp);
 extern json_spirit::Value reconsiderblock(const json_spirit::Array& params, bool fHelp);
@@ -259,4 +256,3 @@ extern json_spirit::Value smsgbroadcast(const json_spirit::Array& params, bool f
 
 #endif
 
-
diff --git a/src/util.cpp b/src/util.cpp
index 0cbed60..ee48cb1 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -33,6 +33,8 @@
 
 #ifndef WIN32
 #include <execinfo.h>
+#include <sys/stat.h>
+#include <unistd.h>
 #endif
 
 #include "util.h"
@@ -174,9 +176,10 @@ uint64_t GetRand(uint64_t nMax)
     // to give every possible output value an equal possibility
     uint64_t nRange = (std::numeric_limits<uint64_t>::max() / nMax) * nMax;
     uint64_t nRand = 0;
-    do
-        RAND_bytes((unsigned char*)&nRand, sizeof(nRand));
-    while (nRand >= nRange);
+    do {
+        if (RAND_bytes(reinterpret_cast<unsigned char*>(&nRand), sizeof(nRand)) != 1)
+            throw std::runtime_error("OpenSSL CSPRNG failure in GetRand");
+    } while (nRand >= nRange);
     return (nRand % nMax);
 }
 
@@ -188,7 +191,8 @@ int GetRandInt(int nMax)
 uint256 GetRandHash()
 {
     uint256 hash;
-    RAND_bytes((unsigned char*)&hash, sizeof(hash));
+    if (RAND_bytes(reinterpret_cast<unsigned char*>(&hash), sizeof(hash)) != 1)
+        throw std::runtime_error("OpenSSL CSPRNG failure in GetRandHash");
     return hash;
 }
 
@@ -616,7 +620,9 @@ bool SoftSetBoolArg(std::string_view strArg, bool fValue)
 
 bool WildcardMatch(std::string_view str, std::string_view mask)
 {
-    return WildcardMatch(std::string(str), std::string(mask));
+    const std::string strOwned(str);
+    const std::string maskOwned(mask);
+    return WildcardMatch(strOwned.c_str(), maskOwned.c_str());
 }
 
 
@@ -954,31 +960,27 @@ string DecodeBase32(const string& str)
 
 bool WildcardMatch(const char* psz, const char* mask)
 {
-    while (true)
-    {
-        switch (*mask)
-        {
-        case '\0':
-            return (*psz == '\0');
-        case '*':
-            return WildcardMatch(psz, mask+1) || (*psz && WildcardMatch(psz+1, mask));
-        case '?':
-            if (*psz == '\0')
-                return false;
-            break;
-        default:
-            if (*psz != *mask)
-                return false;
-            break;
-        }
-        psz++;
-        mask++;
-    }
-}
+    const char* star = nullptr;
+    const char* retry = nullptr;
 
-bool WildcardMatch(const string& str, const string& mask)
-{
-    return WildcardMatch(str.c_str(), mask.c_str());
+    while (*psz != '\0') {
+        if (*mask == '?' || *mask == *psz) {
+            ++psz;
+            ++mask;
+        } else if (*mask == '*') {
+            star = mask++;
+            retry = psz;
+        } else if (star != nullptr) {
+            mask = star + 1;
+            psz = ++retry;
+        } else {
+            return false;
+        }
+    }
+
+    while (*mask == '*')
+        ++mask;
+    return *mask == '\0';
 }
 
 
@@ -1145,7 +1147,20 @@ void ReadConfigFile(map<string, string>& mapSettingsRet,
     //   - Section headers ([section])
     // If any of those become needed, the actual conf syntax in
     // contrib/triangles.conf.example should be extended first.
-    std::ifstream streamConfig(GetConfigFile());
+    const std::filesystem::path configPath = GetConfigFile();
+#ifndef WIN32
+    struct stat configStat;
+    if (::lstat(configPath.string().c_str(), &configStat) == 0) {
+        if (!S_ISREG(configStat.st_mode) || configStat.st_uid != geteuid() ||
+            (configStat.st_mode & (S_IRWXG | S_IRWXO)) != 0) {
+            throw std::runtime_error(
+                "Refusing to read insecure configuration file " + configPath.string() +
+                "; it must be a regular file owned by the current user with no group or other access");
+        }
+    }
+#endif
+
+    std::ifstream streamConfig(configPath);
     if (!streamConfig.good())
         return; // No triangles.conf file is OK
 
diff --git a/src/wallet.cpp b/src/wallet.cpp
index e9c468f..3e7becc 100644
--- a/src/wallet.cpp
+++ b/src/wallet.cpp
@@ -13,12 +13,15 @@
 #include "kernel.h"
 #include "coincontrol.h"
 #include "addressindex.h"
+#include "init.h"
 #include "util.h"
 #include <cstring>
 #include <memory>
 #include <algorithm>
+#include <limits>
 #include <random>
 #include <deque>
+#include <openssl/crypto.h>
 
 using namespace std;
 extern unsigned int nStakeMaxAge;
@@ -26,6 +29,29 @@ extern unsigned int nStakeMaxAge;
 unsigned int nStakeSplitAge = 1 * 3 * 60 * 60;
 int64_t nStakeCombineThreshold = 20 * COIN;
 
+namespace {
+void CleanseWalletString(std::string& value)
+{
+    if (!value.empty())
+        OPENSSL_cleanse(value.data(), value.size());
+    value.clear();
+}
+
+bool RewriteWalletDatabase(const std::string& walletFile, const char* skip = nullptr)
+{
+    if (ResolveWalletDbKind() != WalletDbKind::SQLite)
+        return CDB::Rewrite(walletFile, skip);
+
+    try {
+        CWalletDB walletdb(walletFile);
+        return walletdb.RewriteDatabase(skip);
+    } catch (const std::exception& e) {
+        printf("RewriteWalletDatabase: %s\n", e.what());
+        return false;
+    }
+}
+} // namespace
+
 //////////////////////////////////////////////////////////////////////////////
 //
 // mapWallet
@@ -132,32 +158,80 @@ CPubKey CWallet::GenerateNewKey()
     RandAddSeedPerfmon();
     CKey key;
     bool fUsedHD = false;
-    if (fHDEnabled && !hdMnemonic.empty()) {
-        if (DeriveHDKey(nHDChainIndex, key)) { fUsedHD = true; fCompressed = true; }
+    if (fHDEnabled) {
+        if (hdMnemonic.empty())
+            throw std::runtime_error("CWallet::GenerateNewKey() : HD seed is unavailable while wallet is locked");
+        if (!DeriveHDKey(nHDChainIndex, key))
+            throw std::runtime_error("CWallet::GenerateNewKey() : HD key derivation failed");
+        fUsedHD = true;
+        fCompressed = true;
     }
     if (!fUsedHD)
         key.MakeNewKey(fCompressed);
 
     // Compressed public keys were introduced in version 0.6.0
-    if (fCompressed)
-        SetMinVersion(WalletFeature::ComprPubKey);
+    if (fCompressed && !SetMinVersion(WalletFeature::ComprPubKey))
+        throw std::runtime_error("CWallet::GenerateNewKey() : wallet version update failed");
 
     CPubKey pubkey = key.GetPubKey();
 
-    // Create new metadata
-    int64_t nCreationTime = GetTime();
-    mapKeyMetadata[pubkey.GetID()] = CKeyMetadata(nCreationTime);
+    const int64_t nCreationTime = GetTime();
+    const CKeyMetadata metadata(nCreationTime);
+
+    if (fUsedHD && fFileBacked) {
+        const int64_t nextHDChainIndex = nHDChainIndex + 1;
+        std::vector<unsigned char> cryptedSecret;
+        if (IsCrypted()) {
+            if (IsLocked() || vMasterKey.size() != WALLET_CRYPTO_KEY_SIZE)
+                throw std::runtime_error("CWallet::GenerateNewKey() : encrypted HD wallet is locked");
+            bool compressed = false;
+            if (!EncryptSecret(vMasterKey, key.GetSecret(compressed),
+                               pubkey.GetHash(), cryptedSecret))
+                throw std::runtime_error("CWallet::GenerateNewKey() : key encryption failed");
+        }
+
+        CWalletDB walletdb(strWalletFile);
+        if (!walletdb.TxnBegin())
+            throw std::runtime_error("CWallet::GenerateNewKey() : database transaction failed");
+        bool wrote = IsCrypted()
+            ? walletdb.WriteCryptedKey(pubkey, cryptedSecret, metadata)
+            : walletdb.WriteKey(pubkey, key.GetPrivKey(), metadata);
+        wrote = wrote && walletdb.WriteHDChain(nextHDChainIndex);
+        if (!wrote) {
+            walletdb.TxnAbort();
+            throw std::runtime_error("CWallet::GenerateNewKey() : atomic HD key write failed");
+        }
+        if (!walletdb.TxnCommit()) {
+            walletdb.TxnAbort();
+            throw std::runtime_error("CWallet::GenerateNewKey() : atomic HD key commit failed");
+        }
+
+        const bool added = IsCrypted()
+            ? CCryptoKeyStore::AddCryptedKey(pubkey, cryptedSecret)
+            : CBasicKeyStore::AddKey(key);
+        if (!added) {
+            printf("GenerateNewKey: HD key persisted but could not be added in memory; shutting down\n");
+            MarkShutdownFailure();
+            StartShutdown();
+            throw std::runtime_error("CWallet::GenerateNewKey() : in-memory HD key commit failed");
+        }
+        mapKeyMetadata[pubkey.GetID()] = metadata;
+        if (!nTimeFirstKey || nCreationTime < nTimeFirstKey)
+            nTimeFirstKey = nCreationTime;
+        nHDChainIndex = nextHDChainIndex;
+        return pubkey;
+    }
+
+    mapKeyMetadata[pubkey.GetID()] = metadata;
+    if (!AddKey(key)) {
+        mapKeyMetadata.erase(pubkey.GetID());
+        throw std::runtime_error("CWallet::GenerateNewKey() : AddKey failed");
+    }
     if (!nTimeFirstKey || nCreationTime < nTimeFirstKey)
         nTimeFirstKey = nCreationTime;
-
-    if (!AddKey(key))
-        throw std::runtime_error("CWallet::GenerateNewKey() : AddKey failed");
-    if (fUsedHD) {
-        nHDChainIndex++;
-        if (fFileBacked)
-            CWalletDB(strWalletFile).WriteHDChain(nHDChainIndex);
-    }
-    return key.GetPubKey();
+    if (fUsedHD)
+        ++nHDChainIndex;
+    return pubkey;
 }
 
 bool CWallet::AddKey(const CKey& key)
@@ -215,22 +289,17 @@ bool fWalletUnlockStakingOnly = false;
 
 bool CWallet::Lock()
 {
+    if (IsCrypted()) {
+        CleanseWalletString(hdMnemonic);
+        CleanseWalletString(hdPassphrase);
+    }
+
     if (IsLocked())
         return true;
 
     if (fDebug)
         printf("Locking wallet.\n");
 
-    if (IsCrypted()) {
-        hdMnemonic.clear();   // keep only the encrypted copies while locked
-        hdPassphrase.clear();
-    }
-
-    {
-        LOCK(cs_wallet);
-        CWalletDB wdb(strWalletFile);
-
-    }
     return LockKeyStore();
 };
 
@@ -242,38 +311,66 @@ bool CWallet::Unlock(const SecureString& strWalletPassphrase)
     CCrypter crypter;
     CKeyingMaterial vMasterKey;
 
+    bool unlocked = false;
     {
         LOCK(cs_wallet);
         for (const MasterKeyMap::value_type& pMasterKey : mapMasterKeys)
         {
             if(!crypter.SetKeyFromPassphrase(strWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod))
-                return false;
+                continue;
             if (!crypter.Decrypt(pMasterKey.second.vchCryptedKey, vMasterKey))
-                return false;
+                continue;
             if (CCryptoKeyStore::Unlock(vMasterKey)) {
-                if (fHDEnabled && hdMnemonic.empty() && !vchCryptedHDMnemonic.empty()) {
+                if (fHDEnabled) {
+                    if (vchCryptedHDMnemonic.empty()) {
+                        LockKeyStore();
+                        return false;
+                    }
                     CSecret sec;
-                    if (DecryptSecret(vMasterKey, vchCryptedHDMnemonic, hdMnemonicIV, sec))
-                        hdMnemonic.assign(sec.begin(), sec.end());
+                    if (!DecryptSecret(vMasterKey, vchCryptedHDMnemonic, hdMnemonicIV, sec)) {
+                        LockKeyStore();
+                        return false;
+                    }
+                    std::string mnemonic(sec.begin(), sec.end());
+                    if (!hd::CheckMnemonic(mnemonic)) {
+                        OPENSSL_cleanse(mnemonic.data(), mnemonic.size());
+                        LockKeyStore();
+                        return false;
+                    }
+
+                    std::string passphrase;
+                    if (!vchCryptedHDPassphrase.empty()) {
+                        CSecret psec;
+                        if (!DecryptSecret(vMasterKey, vchCryptedHDPassphrase,
+                                           hdPassphraseIV, psec)) {
+                            OPENSSL_cleanse(mnemonic.data(), mnemonic.size());
+                            LockKeyStore();
+                            return false;
+                        }
+                        passphrase.assign(psec.begin(), psec.end());
+                    }
+
+                    CleanseWalletString(hdMnemonic);
+                    CleanseWalletString(hdPassphrase);
+                    hdMnemonic = std::move(mnemonic);
+                    hdPassphrase = std::move(passphrase);
                 }
-                if (fHDEnabled && hdPassphrase.empty() && !vchCryptedHDPassphrase.empty()) {
-                    CSecret psec;
-                    if (DecryptSecret(vMasterKey, vchCryptedHDPassphrase, hdPassphraseIV, psec))
-                        hdPassphrase.assign(psec.begin(), psec.end());
-                }
-                return true;
+                unlocked = true;
+                break;
             }
         }
-
-        SecureMsgWalletUnlocked();
-        return true;
     }
-    return false;
+    if (!unlocked)
+        return false;
+
+    SecureMsgWalletUnlocked();
+    return true;
 }
 
 bool CWallet::ChangeWalletPassphrase(const SecureString& strOldWalletPassphrase, const SecureString& strNewWalletPassphrase)
 {
-    bool fWasLocked = IsLocked();
+    const bool fWasLocked = IsLocked();
+    bool changed = false;
 
     {
         LOCK(cs_wallet);
@@ -284,39 +381,73 @@ bool CWallet::ChangeWalletPassphrase(const SecureString& strOldWalletPassphrase,
         for (MasterKeyMap::value_type& pMasterKey : mapMasterKeys)
         {
             if(!crypter.SetKeyFromPassphrase(strOldWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod))
-                return false;
+                continue;
             if (!crypter.Decrypt(pMasterKey.second.vchCryptedKey, vMasterKey))
-                return false;
+                continue;
             if (CCryptoKeyStore::Unlock(vMasterKey))
             {
+                CMasterKey updatedMasterKey = pMasterKey.second;
                 int64_t nStartTime = GetTimeMillis();
-                crypter.SetKeyFromPassphrase(strNewWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod);
+                if (!crypter.SetKeyFromPassphrase(strNewWalletPassphrase,
+                                                  updatedMasterKey.vchSalt,
+                                                  updatedMasterKey.nDeriveIterations,
+                                                  updatedMasterKey.nDerivationMethod))
+                    break;
                 int64_t nElapsed = std::max((int64_t)1, GetTimeMillis() - nStartTime);
-                pMasterKey.second.nDeriveIterations = pMasterKey.second.nDeriveIterations * (100 / ((double)nElapsed));
+                updatedMasterKey.nDeriveIterations =
+                    updatedMasterKey.nDeriveIterations * (100 / ((double)nElapsed));
 
                 nStartTime = GetTimeMillis();
-                crypter.SetKeyFromPassphrase(strNewWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod);
+                if (!crypter.SetKeyFromPassphrase(strNewWalletPassphrase,
+                                                  updatedMasterKey.vchSalt,
+                                                  updatedMasterKey.nDeriveIterations,
+                                                  updatedMasterKey.nDerivationMethod))
+                    break;
                 nElapsed = std::max((int64_t)1, GetTimeMillis() - nStartTime);
-                pMasterKey.second.nDeriveIterations = (pMasterKey.second.nDeriveIterations + pMasterKey.second.nDeriveIterations * 100 / ((double)nElapsed)) / 2;
+                updatedMasterKey.nDeriveIterations =
+                    (updatedMasterKey.nDeriveIterations +
+                     updatedMasterKey.nDeriveIterations * 100 / ((double)nElapsed)) / 2;
 
-                if (pMasterKey.second.nDeriveIterations < 25000)
-                    pMasterKey.second.nDeriveIterations = 25000;
+                if (updatedMasterKey.nDeriveIterations < 25000)
+                    updatedMasterKey.nDeriveIterations = 25000;
 
-                printf("Wallet passphrase changed to an nDeriveIterations of %i\n", pMasterKey.second.nDeriveIterations);
+                printf("Wallet passphrase changed to an nDeriveIterations of %i\n",
+                       updatedMasterKey.nDeriveIterations);
 
-                if (!crypter.SetKeyFromPassphrase(strNewWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod))
-                    return false;
-                if (!crypter.Encrypt(vMasterKey, pMasterKey.second.vchCryptedKey))
-                    return false;
-                CWalletDB(strWalletFile).WriteMasterKey(pMasterKey.first, pMasterKey.second);
-                if (fWasLocked)
-                    Lock();
-                return true;
+                if (!crypter.SetKeyFromPassphrase(strNewWalletPassphrase,
+                                                  updatedMasterKey.vchSalt,
+                                                  updatedMasterKey.nDeriveIterations,
+                                                  updatedMasterKey.nDerivationMethod))
+                    break;
+                if (!crypter.Encrypt(vMasterKey, updatedMasterKey.vchCryptedKey))
+                    break;
+
+                bool persisted = true;
+                if (fFileBacked) {
+                    try {
+                        persisted = CWalletDB(strWalletFile).WriteMasterKey(
+                            pMasterKey.first, updatedMasterKey);
+                    } catch (const std::exception& e) {
+                        printf("ChangeWalletPassphrase: %s\n", e.what());
+                        persisted = false;
+                    }
+                }
+                if (!persisted)
+                    break;
+
+                pMasterKey.second = std::move(updatedMasterKey);
+                changed = true;
+                break;
             }
         }
+        LockKeyStore();
     }
 
-    return false;
+    if (!changed)
+        return false;
+    if (!fWasLocked && !Unlock(strNewWalletPassphrase))
+        return false;
+    return true;
 }
 
 void CWallet::SetBestChain(const CBlockLocator& loc)
@@ -346,27 +477,44 @@ bool CWallet::SetMinVersion(WalletFeature nVersion, CWalletDB* pwalletdbIn, bool
     if (fExplicit && static_cast<int>(nVersion) > nWalletMaxVersion)
             nVersion = WalletFeature::Latest;
 
-    nWalletVersion = static_cast<int>(nVersion);
-
-    if (static_cast<int>(nVersion) > nWalletMaxVersion)
-        nWalletMaxVersion = static_cast<int>(nVersion);
+    const int newWalletVersion = static_cast<int>(nVersion);
 
     if (fFileBacked)
     {
-        CWalletDB* pwalletdb = pwalletdbIn ? pwalletdbIn : new CWalletDB(strWalletFile);
-        if (nWalletVersion >= 40000)
+        std::unique_ptr<CWalletDB> ownedWalletDB;
+        CWalletDB* pwalletdb = pwalletdbIn;
+        if (!pwalletdb) {
+            ownedWalletDB = std::make_unique<CWalletDB>(strWalletFile);
+            pwalletdb = ownedWalletDB.get();
+            if (!pwalletdb->TxnBegin())
+                return false;
+        }
+
+        bool wrote = true;
+        if (newWalletVersion >= 40000)
         {
             // Versions prior to 0.4.0 did not support the "minversion" record.
             // Use a CCorruptAddress to make them crash instead.
             CCorruptAddress corruptAddress;
-            pwalletdb->WriteSetting("addrIncoming", corruptAddress);
+            wrote = pwalletdb->WriteSetting("addrIncoming", corruptAddress);
+        }
+        if (wrote && newWalletVersion > 40000)
+            wrote = pwalletdb->WriteMinVersion(newWalletVersion);
+
+        if (!wrote) {
+            if (ownedWalletDB)
+                pwalletdb->TxnAbort();
+            return false;
+        }
+        if (ownedWalletDB && !pwalletdb->TxnCommit()) {
+            pwalletdb->TxnAbort();
+            return false;
         }
-        if (nWalletVersion > 40000)
-            pwalletdb->WriteMinVersion(nWalletVersion);
-        if (!pwalletdbIn)
-            delete pwalletdb;
     }
 
+    nWalletVersion = newWalletVersion;
+    if (newWalletVersion > nWalletMaxVersion)
+        nWalletMaxVersion = newWalletVersion;
     return true;
 }
 
@@ -385,27 +533,38 @@ bool CWallet::EncryptWallet(const SecureString& strWalletPassphrase)
 {
     if (IsCrypted())
         return false;
+    if (fHDEnabled && hdMnemonic.empty())
+        return false;
+    if (nMasterKeyMaxID == std::numeric_limits<unsigned int>::max())
+        return false;
 
     CKeyingMaterial vMasterKey;
     RandAddSeedPerfmon();
 
     vMasterKey.resize(WALLET_CRYPTO_KEY_SIZE);
-    RAND_bytes(&vMasterKey[0], WALLET_CRYPTO_KEY_SIZE);
+    if (RAND_bytes(&vMasterKey[0], WALLET_CRYPTO_KEY_SIZE) != 1)
+        return false;
 
     CMasterKey kMasterKey(nDerivationMethodIndex);
 
     RandAddSeedPerfmon();
     kMasterKey.vchSalt.resize(WALLET_CRYPTO_SALT_SIZE);
-    RAND_bytes(&kMasterKey.vchSalt[0], WALLET_CRYPTO_SALT_SIZE);
+    if (RAND_bytes(&kMasterKey.vchSalt[0], WALLET_CRYPTO_SALT_SIZE) != 1)
+        return false;
 
     CCrypter crypter;
     int64_t nStartTime = GetTimeMillis();
-    crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt, 25000, kMasterKey.nDerivationMethod);
+    if (!crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt,
+                                      25000, kMasterKey.nDerivationMethod))
+        return false;
     int64_t nElapsed = std::max((int64_t)1, GetTimeMillis() - nStartTime);
     kMasterKey.nDeriveIterations = 2500000 / ((double)nElapsed);
 
     nStartTime = GetTimeMillis();
-    crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt, kMasterKey.nDeriveIterations, kMasterKey.nDerivationMethod);
+    if (!crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt,
+                                      kMasterKey.nDeriveIterations,
+                                      kMasterKey.nDerivationMethod))
+        return false;
     nElapsed = std::max((int64_t)1, GetTimeMillis() - nStartTime);
     kMasterKey.nDeriveIterations = (kMasterKey.nDeriveIterations + kMasterKey.nDeriveIterations * 100 / ((double)nElapsed)) / 2;
 
@@ -421,51 +580,109 @@ bool CWallet::EncryptWallet(const SecureString& strWalletPassphrase)
 
     {
         LOCK(cs_wallet);
-        mapMasterKeys[++nMasterKeyMaxID] = kMasterKey;
+        CryptedKeyMap cryptedKeys;
+        if (!PrepareKeyEncryption(vMasterKey, cryptedKeys))
+            return false;
+
+        uint256 newMnemonicIV;
+        uint256 newPassphraseIV;
+        std::vector<unsigned char> newCryptedMnemonic;
+        std::vector<unsigned char> newCryptedPassphrase;
+        if (fHDEnabled) {
+            CSecret mnemonicSecret(hdMnemonic.begin(), hdMnemonic.end());
+            newMnemonicIV = GetRandHash();
+            if (!EncryptSecret(vMasterKey, mnemonicSecret, newMnemonicIV,
+                               newCryptedMnemonic))
+                return false;
+            if (!hdPassphrase.empty()) {
+                CSecret passphraseSecret(hdPassphrase.begin(), hdPassphrase.end());
+                newPassphraseIV = GetRandHash();
+                if (!EncryptSecret(vMasterKey, passphraseSecret, newPassphraseIV,
+                                   newCryptedPassphrase))
+                    return false;
+            }
+        }
+
+        const unsigned int newMasterKeyID = nMasterKeyMaxID + 1;
+        const int oldWalletVersion = nWalletVersion;
+        const int oldWalletMaxVersion = nWalletMaxVersion;
         if (fFileBacked)
         {
-            std::unique_ptr<CWalletDB> dbEnc(new CWalletDB(strWalletFile));
+            std::unique_ptr<CWalletDB> dbEnc = std::make_unique<CWalletDB>(strWalletFile);
             if (!dbEnc->TxnBegin())
                 return false;
-            dbEnc->WriteMasterKey(nMasterKeyMaxID, kMasterKey);
+            bool wrote = dbEnc->WriteMasterKey(newMasterKeyID, kMasterKey);
+            for (const auto& item : cryptedKeys) {
+                if (!wrote)
+                    break;
+                CKeyMetadata metadata;
+                auto metadataIt = mapKeyMetadata.find(item.first);
+                if (metadataIt != mapKeyMetadata.end())
+                    metadata = metadataIt->second;
+                wrote = dbEnc->WriteCryptedKey(item.second.first,
+                                               item.second.second, metadata);
+            }
+            if (wrote && fHDEnabled) {
+                wrote = dbEnc->WriteHDCryptedMnemonic(newMnemonicIV,
+                                                      newCryptedMnemonic);
+                if (wrote) {
+                    wrote = hdPassphrase.empty()
+                        ? dbEnc->EraseHDPassphrase()
+                        : dbEnc->WriteHDCryptedPassphrase(newPassphraseIV,
+                                                         newCryptedPassphrase);
+                }
+            }
+            if (wrote)
+                wrote = SetMinVersion(WalletFeature::WalletCrypt, dbEnc.get(), true);
 
-            if (!EncryptKeys(vMasterKey))
-            {
+            if (!wrote) {
                 dbEnc->TxnAbort();
+                nWalletVersion = oldWalletVersion;
+                nWalletMaxVersion = oldWalletMaxVersion;
                 return false;
             }
-
-            if (fHDEnabled && !hdMnemonic.empty()) {
-                CSecret sec(hdMnemonic.begin(), hdMnemonic.end());
-                uint256 iv = GetRandHash();
-                std::vector<unsigned char> cipher;
-                if (!EncryptSecret(vMasterKey, sec, iv, cipher)) { dbEnc->TxnAbort(); return false; }
-                hdMnemonicIV = iv; vchCryptedHDMnemonic = cipher;
-                dbEnc->WriteHDCryptedMnemonic(iv, cipher);
-            }
-            if (fHDEnabled && !hdPassphrase.empty()) {
-                CSecret psec(hdPassphrase.begin(), hdPassphrase.end());
-                uint256 piv = GetRandHash();
-                std::vector<unsigned char> pcipher;
-                if (!EncryptSecret(vMasterKey, psec, piv, pcipher)) { dbEnc->TxnAbort(); return false; }
-                hdPassphraseIV = piv; vchCryptedHDPassphrase = pcipher;
-                dbEnc->WriteHDCryptedPassphrase(piv, pcipher);
-            }
-
-            SetMinVersion(WalletFeature::WalletCrypt, dbEnc.get(), true);
-
-            if (!dbEnc->TxnCommit())
+            if (!dbEnc->TxnCommit()) {
+                dbEnc->TxnAbort();
+                nWalletVersion = oldWalletVersion;
+                nWalletMaxVersion = oldWalletMaxVersion;
                 return false;
+            }
+        } else if (!SetMinVersion(WalletFeature::WalletCrypt, nullptr, true)) {
+            return false;
+        }
+
+        if (!CommitKeyEncryption(std::move(cryptedKeys))) {
+            printf("EncryptWallet: disk was updated but in-memory key encryption could not be committed; shutting down\n");
+            MarkShutdownFailure();
+            StartShutdown();
+            return false;
+        }
+        nMasterKeyMaxID = newMasterKeyID;
+        mapMasterKeys[newMasterKeyID] = kMasterKey;
+        if (fHDEnabled) {
+            hdMnemonicIV = newMnemonicIV;
+            hdPassphraseIV = newPassphraseIV;
+            vchCryptedHDMnemonic = std::move(newCryptedMnemonic);
+            vchCryptedHDPassphrase = std::move(newCryptedPassphrase);
         }
 
         Lock();
-        Unlock(strWalletPassphrase);
-        NewKeyPool();
+        if (!Unlock(strWalletPassphrase)) {
+            printf("EncryptWallet: encrypted wallet could not be verified; shutting down\n");
+            MarkShutdownFailure();
+            StartShutdown();
+            return false;
+        }
+        if (!NewKeyPool())
+            printf("EncryptWallet: wallet encrypted, but keypool regeneration failed\n");
         Lock();
 
-        // Need to completely rewrite the wallet file; if we don't, bdb might keep
-        // bits of the unencrypted private key in slack space in the database file.
-        CDB::Rewrite(strWalletFile);
+        if (fFileBacked && !RewriteWalletDatabase(strWalletFile)) {
+            printf("EncryptWallet: secure wallet database rewrite failed; shutting down\n");
+            MarkShutdownFailure();
+            StartShutdown();
+            return false;
+        }
 
     }
     NotifyStatusChanged(this);
@@ -793,7 +1010,7 @@ bool CWallet::AbandonTransaction(const uint256& hashTx)
     // the inputs (vfSpent was tracked on the wtx) and resolves the conflict.
     bool fErased = EraseFromWallet(hashTx);
 
-    LogPrintf("CWallet::AbandonTransaction: %s abandoned (%u descendant(s) noted)\n",
+    LogPrintf("CWallet::AbandonTransaction: %s abandoned (%" PRIszu " descendant(s) noted)\n",
               hashTx.ToString().c_str(), sDescendants.size());
     return fErased;
 }
@@ -2115,10 +2332,12 @@ bool CWallet::CreateCoinStake(const CKeyStore& keystore, unsigned int nBits, int
                         break;  // unable to find corresponding public key
                     }
 
-                if (key.GetPubKey() != vchPubKey)
-                {
-                    if (fDebug && GetBoolArg("-printcoinstake"))
-                        printf("CreateCoinStake : invalid key for kernel type=%d\n", whichType);
+                    if (key.GetPubKey() != vchPubKey)
+                    {
+                        if (fDebug && GetBoolArg("-printcoinstake")) {
+                            printf("CreateCoinStake : invalid key for kernel type=%d\n",
+                                   static_cast<int>(whichType));
+                        }
                         break; // keys mismatch
                     }
 
@@ -2134,7 +2353,7 @@ bool CWallet::CreateCoinStake(const CKeyStore& keystore, unsigned int nBits, int
                 if (GetWeight(block.GetBlockTime(), (int64_t)txNew.nTime) < nStakeSplitAge)
                     txNew.vout.push_back(CTxOut(0, scriptPubKeyOut)); //split stake
                 if (fDebug && GetBoolArg("-printcoinstake"))
-                    printf("CreateCoinStake : added kernel type=%d\n", whichType);
+                    printf("CreateCoinStake : added kernel type=%d\n", static_cast<int>(whichType));
                 fKernelFound = true;
                 break;
             }
@@ -2351,7 +2570,7 @@ DBErrors CWallet::LoadWallet(bool& fFirstRunRet)
     DBErrors nLoadWalletRet = CWalletDB(strWalletFile,"cr+").LoadWallet(this);
     if (nLoadWalletRet == DB_NEED_REWRITE)
     {
-        if (CDB::Rewrite(strWalletFile, "\x04pool"))
+        if (RewriteWalletDatabase(strWalletFile, "\x04pool"))
         {
             setKeyPool.clear();
             // Note: can't top-up keypool here, because wallet is locked.
@@ -2478,9 +2697,13 @@ bool CWallet::NewKeyPool()
 {
     {
         LOCK(cs_wallet);
-        CWalletDB walletdb(strWalletFile);
-        for (int64_t nIndex : setKeyPool)
-            walletdb.ErasePool(nIndex);
+        std::unique_ptr<CWalletDB> walletdb;
+        if (fFileBacked)
+            walletdb = std::make_unique<CWalletDB>(strWalletFile);
+        for (int64_t nIndex : setKeyPool) {
+            if (walletdb && !walletdb->ErasePool(nIndex))
+                return false;
+        }
         setKeyPool.clear();
 
         if (IsLocked())
@@ -2490,7 +2713,9 @@ bool CWallet::NewKeyPool()
         for (int i = 0; i < nKeys; i++)
         {
             int64_t nIndex = i+1;
-            walletdb.WritePool(nIndex, CKeyPool(GenerateNewKey()));
+            CKeyPool keypool(GenerateNewKey());
+            if (walletdb && !walletdb->WritePool(nIndex, keypool))
+                return false;
             setKeyPool.insert(nIndex);
         }
         printf("CWallet::NewKeyPool wrote %"PRId64" new keys\n", nKeys);
@@ -2506,7 +2731,9 @@ bool CWallet::TopUpKeyPool(unsigned int nSize)
         if (IsLocked())
             return false;
 
-        CWalletDB walletdb(strWalletFile);
+        std::unique_ptr<CWalletDB> walletdb;
+        if (fFileBacked)
+            walletdb = std::make_unique<CWalletDB>(strWalletFile);
 
         // Top up key pool
         unsigned int nTargetSize;
@@ -2520,7 +2747,8 @@ bool CWallet::TopUpKeyPool(unsigned int nSize)
             int64_t nEnd = 1;
             if (!setKeyPool.empty())
                 nEnd = *(--setKeyPool.end()) + 1;
-            if (!walletdb.WritePool(nEnd, CKeyPool(GenerateNewKey())))
+            CKeyPool keypool(GenerateNewKey());
+            if (walletdb && !walletdb->WritePool(nEnd, keypool))
                 throw runtime_error("TopUpKeyPool() : writing generated key failed");
             setKeyPool.insert(nEnd);
             printf("keypool added key %"PRId64", size=%"PRIszu"\n", nEnd, setKeyPool.size());
@@ -2946,16 +3174,18 @@ void CWallet::GetKeyBirthTimes(std::map<CKeyID, int64_t> &mapKeyBirth) const {
 // ---- HD wallet (BIP39/BIP32) implementation ----
 bool CWallet::DeriveHDKey(int64_t index, CKey& keyOut) const
 {
-    if (hdMnemonic.empty())
+    if (hdMnemonic.empty() || index < 0 ||
+        static_cast<uint64_t>(index) > std::numeric_limits<uint32_t>::max())
         return false;
     // If a BIP39 passphrase ("25th word") was set with the seed, it MUST be
     // part of every derivation — otherwise restored wallets derive different
     // addresses than the originals. Empty string = no passphrase (legacy).
     unsigned char priv[32];
-    if (!hd::DeriveTriangles(hdMnemonic, hdPassphrase, 0, 0, (uint32_t)index, priv))
+    if (!hd::DeriveTriangles(hdMnemonic, hdPassphrase, 0, 0,
+                             static_cast<uint32_t>(index), priv))
         return false;
     CSecret secret(priv, priv + 32);
-    memset(priv, 0, sizeof(priv));
+    OPENSSL_cleanse(priv, sizeof(priv));
     keyOut.SetSecret(secret, true); // HD keys are compressed
     return true;
 }
@@ -2972,6 +3202,7 @@ bool CWallet::SetHDSeed(const std::string& mnemonicIn, const std::string& passph
 {
     LOCK(cs_wallet);
     if (IsLocked()) { strError = "Wallet is locked; unlock it before setting an HD seed."; return false; }
+    if (fHDEnabled) { strError = "Wallet already has an HD seed; refusing to replace it."; return false; }
 
     std::string m = mnemonicIn;
     if (m.empty()) {
@@ -2983,45 +3214,86 @@ bool CWallet::SetHDSeed(const std::string& mnemonicIn, const std::string& passph
 
     unsigned char priv[32];
     if (!hd::DeriveTriangles(m, passphrase, 0, 0, 0, priv)) { strError = "Key derivation failed."; return false; }
-    memset(priv, 0, sizeof(priv));
+    OPENSSL_cleanse(priv, sizeof(priv));
 
-    hdMnemonic = m;
-    hdPassphrase = passphrase;
-    fHDEnabled = true;
-    nHDChainIndex = 0;
+    uint256 newMnemonicIV;
+    uint256 newPassphraseIV;
+    std::vector<unsigned char> newCryptedMnemonic;
+    std::vector<unsigned char> newCryptedPassphrase;
+
+    if (IsCrypted()) {
+        if (vMasterKey.size() != WALLET_CRYPTO_KEY_SIZE) {
+            strError = "Wallet master key is unavailable.";
+            return false;
+        }
+        CSecret sec(m.begin(), m.end());
+        newMnemonicIV = GetRandHash();
+        if (!EncryptSecret(vMasterKey, sec, newMnemonicIV, newCryptedMnemonic)) {
+            strError = "Failed to encrypt seed.";
+            return false;
+        }
+        if (!passphrase.empty()) {
+            CSecret psec(passphrase.begin(), passphrase.end());
+            newPassphraseIV = GetRandHash();
+            if (!EncryptSecret(vMasterKey, psec, newPassphraseIV,
+                               newCryptedPassphrase)) {
+                strError = "Failed to encrypt passphrase.";
+                return false;
+            }
+        }
+    }
 
     if (fFileBacked) {
         CWalletDB wdb(strWalletFile);
-        if (IsCrypted()) {
-            CSecret sec(m.begin(), m.end());
-            uint256 iv = GetRandHash();
-            std::vector<unsigned char> cipher;
-            if (!EncryptSecret(vMasterKey, sec, iv, cipher)) { strError = "Failed to encrypt seed."; return false; }
-            hdMnemonicIV = iv; vchCryptedHDMnemonic = cipher;
-            wdb.WriteHDCryptedMnemonic(iv, cipher);
-            if (!passphrase.empty()) {
-                CSecret psec(passphrase.begin(), passphrase.end());
-                uint256 piv = GetRandHash();
-                std::vector<unsigned char> pcipher;
-                if (!EncryptSecret(vMasterKey, psec, piv, pcipher)) { strError = "Failed to encrypt passphrase."; return false; }
-                hdPassphraseIV = piv; vchCryptedHDPassphrase = pcipher;
-                wdb.WriteHDCryptedPassphrase(piv, pcipher);
-            } else {
-                vchCryptedHDPassphrase.clear();
-                wdb.EraseHDPassphrase(); // re-seed without passphrase: drop any old record
-            }
-        } else {
-            wdb.WriteHDMnemonic(m);
-            if (!passphrase.empty())
-                wdb.WriteHDPassphrase(passphrase);
-            else
-                wdb.EraseHDPassphrase();
+        if (!wdb.TxnBegin()) {
+            strError = "Failed to start wallet database transaction.";
+            return false;
+        }
+
+        bool wrote = false;
+        if (IsCrypted()) {
+            wrote = wdb.WriteHDCryptedMnemonic(newMnemonicIV, newCryptedMnemonic) &&
+                    (passphrase.empty()
+                         ? wdb.EraseHDPassphrase()
+                         : wdb.WriteHDCryptedPassphrase(newPassphraseIV,
+                                                       newCryptedPassphrase));
+        } else {
+            wrote = wdb.WriteHDMnemonic(m) &&
+                    (passphrase.empty()
+                         ? wdb.EraseHDPassphrase()
+                         : wdb.WriteHDPassphrase(passphrase));
+        }
+        wrote = wrote && wdb.WriteHDChain(0);
+
+        if (!wrote) {
+            wdb.TxnAbort();
+            strError = "Failed to persist HD seed; wallet database transaction was rolled back.";
+            return false;
+        }
+        if (!wdb.TxnCommit()) {
+            wdb.TxnAbort();
+            strError = "Failed to commit HD seed to the wallet database.";
+            return false;
         }
-        wdb.WriteHDChain(nHDChainIndex);
     }
+
+    CleanseWalletString(hdMnemonic);
+    CleanseWalletString(hdPassphrase);
+    hdMnemonic = m;
+    hdPassphrase = passphrase;
+    hdMnemonicIV = newMnemonicIV;
+    hdPassphraseIV = newPassphraseIV;
+    vchCryptedHDMnemonic = std::move(newCryptedMnemonic);
+    vchCryptedHDPassphrase = std::move(newCryptedPassphrase);
+    fHDEnabled = true;
+    nHDChainIndex = 0;
+
     // Replace any pre-existing (random) keypool with HD-derived keys so that
     // getnewaddress immediately hands out deterministic m/44'/2222'/0'/0/i keys.
-    NewKeyPool();
+    if (!NewKeyPool()) {
+        strError = "HD seed was stored, but rebuilding the keypool failed.";
+        return false;
+    }
     mnemonicOut = m;
     return true;
 }
diff --git a/src/wallet.h b/src/wallet.h
index f5329dd..c654c5d 100644
--- a/src/wallet.h
+++ b/src/wallet.h
@@ -76,8 +76,6 @@ private:
     bool SelectCoinsSimple(int64_t nTargetValue, unsigned int nSpendTime, int nMinConf, std::set<std::pair<const CWalletTx*,unsigned int> >& setCoinsRet, int64_t& nValueRet) const;
     bool SelectCoins(int64_t nTargetValue, unsigned int nSpendTime, std::set<std::pair<const CWalletTx*,unsigned int> >& setCoinsRet, int64_t& nValueRet, const CCoinControl *coinControl=nullptr) const;
 
-    CWalletDB *pwalletdbEncryption;
-
     // the current wallet version: clients below this version are not able to load the wallet
     int nWalletVersion;
 
@@ -104,9 +102,9 @@ public:
         nWalletMaxVersion = static_cast<int>(WalletFeature::Base);
         fFileBacked = false;
         nMasterKeyMaxID = 0;
-        pwalletdbEncryption = nullptr;
         fHDEnabled = false;
         nHDChainIndex = 0;
+        nTimeFirstKey = 0;
         nOrderPosNext = 0;
         nCachedStakeWeight = 0;
         nCachedStakeWeightTime = 0;
diff --git a/src/walletdb-sqlite.cpp b/src/walletdb-sqlite.cpp
index 4f68642..3e90257 100644
--- a/src/walletdb-sqlite.cpp
+++ b/src/walletdb-sqlite.cpp
@@ -71,6 +71,9 @@ bool SQLiteDatabase::Open(std::string& strError)
     // Durability + integrity pragmas. FULL fsync on commit — a wallet must not
     // lose a freshly-written key on power loss.
     if (!ExecOrError("PRAGMA synchronous = FULL;", strError)) return false;
+    if (!ExecOrError("PRAGMA journal_mode = DELETE;", strError)) return false;
+    if (!ExecOrError("PRAGMA secure_delete = ON;", strError)) return false;
+    if (!ExecOrError("PRAGMA temp_store = MEMORY;", strError)) return false;
     if (!ExecOrError("PRAGMA foreign_keys = ON;", strError)) return false;
     // Fail loudly instead of silently truncating an over-long blob.
     if (!ExecOrError("PRAGMA cell_size_check = ON;", strError)) return false;
@@ -156,6 +159,20 @@ bool SQLiteDatabase::Backup(const std::string& strDest) const
         if (pDest) sqlite3_close(pDest);
         return false;
     }
+#ifndef WIN32
+    {
+        std::error_code ec;
+        fs::permissions(strDest,
+                        fs::perms::owner_read | fs::perms::owner_write,
+                        fs::perm_options::replace, ec);
+        if (ec) {
+            printf("SQLiteDatabase::Backup cannot restrict destination permissions: %s\n",
+                   ec.message().c_str());
+            sqlite3_close(pDest);
+            return false;
+        }
+    }
+#endif
 
     sqlite3_backup* bk = sqlite3_backup_init(pDest, "main", m_db, "main");
     bool ok = false;
diff --git a/src/walletdb.cpp b/src/walletdb.cpp
index 2a4b4cd..d7590b3 100644
--- a/src/walletdb.cpp
+++ b/src/walletdb.cpp
@@ -42,6 +42,20 @@ namespace fs = std::filesystem;
 static uint64_t nAccountingEntryNumber = 0;
 extern bool fWalletUnlockStakingOnly;
 
+static bool RestrictWalletFilePermissions(const fs::path& path)
+{
+#ifdef WIN32
+    (void)path;
+    return true;
+#else
+    std::error_code ec;
+    fs::permissions(path,
+                    fs::perms::owner_read | fs::perms::owner_write,
+                    fs::perm_options::replace, ec);
+    return !ec;
+#endif
+}
+
 //
 // Auto-backup wallet before flush/rewrite operations.
 // Copies wallet.dat to wallet.dat.auto.bak if the backup is older than the wallet.
@@ -61,10 +75,17 @@ bool AutoBackupWallet(const fs::path& walletPath)
         }
         if (fs::exists(backupPath)) {
             uintmax_t backupSize = fs::file_size(backupPath);
-            if (backupSize == walletSize)
+            if (backupSize == walletSize) {
+                if (!RestrictWalletFilePermissions(backupPath))
+                    return false;
                 return true;
+            }
         }
         fs::copy_file(walletPath, backupPath, fs::copy_options::overwrite_existing);
+        if (!RestrictWalletFilePermissions(backupPath)) {
+            printf("AutoBackupWallet: could not restrict backup file permissions\n");
+            return false;
+        }
         printf("AutoBackupWallet: backed up wallet.dat (%llu bytes) to wallet.dat.auto.bak\n",
                (unsigned long long)walletSize);
         return true;
@@ -257,6 +278,10 @@ public:
     unsigned int nKeyMeta;
     bool fIsEncrypted;
     bool fAnyUnordered;
+    bool fHDPlainMnemonic;
+    bool fHDCryptedMnemonic;
+    bool fHDPlainPassphrase;
+    bool fHDCryptedPassphrase;
     int nFileVersion;
     std::vector<uint256> vWalletUpgrade;
 
@@ -264,6 +289,10 @@ public:
         nKeys = nCKeys = nKeyMeta = 0;
         fIsEncrypted = false;
         fAnyUnordered = false;
+        fHDPlainMnemonic = false;
+        fHDCryptedMnemonic = false;
+        fHDPlainPassphrase = false;
+        fHDCryptedPassphrase = false;
         nFileVersion = 0;
     }
 };
@@ -380,6 +409,7 @@ static bool ReadKeyValue(CWallet* pwallet, CDataStream& ssKey, CDataStream& ssVa
                 return false;
             }
             pwallet->mapMasterKeys[nID] = kMasterKey;
+            wss.fIsEncrypted = true;
             if (pwallet->nMasterKeyMaxID < nID)
                 pwallet->nMasterKeyMaxID = nID;
         } else if (strType == "ckey") {
@@ -417,18 +447,22 @@ static bool ReadKeyValue(CWallet* pwallet, CDataStream& ssKey, CDataStream& ssVa
         } else if (strType == "hdmnemonic") {
             std::string m;
             ssValue >> m;
+            wss.fHDPlainMnemonic = true;
             pwallet->LoadHDMnemonic(m);
         } else if (strType == "hdcmnemonic") {
             std::pair<uint256, std::vector<unsigned char>> cm;
             ssValue >> cm;
+            wss.fHDCryptedMnemonic = true;
             pwallet->LoadCryptedHDMnemonic(cm.first, cm.second);
         } else if (strType == "hdpassphrase") {
             std::string p;
             ssValue >> p;
+            wss.fHDPlainPassphrase = true;
             pwallet->LoadHDPassphrase(p);
         } else if (strType == "hdcpassphrase") {
             std::pair<uint256, std::vector<unsigned char>> cp;
             ssValue >> cp;
+            wss.fHDCryptedPassphrase = true;
             pwallet->LoadCryptedHDPassphrase(cp.first, cp.second);
         } else if (strType == "hdchain") {
             int64_t n;
@@ -513,6 +547,35 @@ DBErrors CWalletDB::LoadWallet(CWallet* pwallet)
     if (fNoncriticalErrors && result == DB_LOAD_OK)
         result = DB_NONCRITICAL_ERROR;
 
+    if (result != DB_LOAD_OK && result != DB_NONCRITICAL_ERROR)
+        return result;
+
+    const bool conflictingMnemonicRecords =
+        wss.fHDPlainMnemonic && wss.fHDCryptedMnemonic;
+    const bool conflictingPassphraseRecords =
+        wss.fHDPlainPassphrase && wss.fHDCryptedPassphrase;
+    const bool missingMnemonic =
+        (wss.fHDPlainPassphrase || wss.fHDCryptedPassphrase) &&
+        !(wss.fHDPlainMnemonic || wss.fHDCryptedMnemonic);
+    const bool mixedHDProtection =
+        (wss.fHDPlainMnemonic && wss.fHDCryptedPassphrase) ||
+        (wss.fHDCryptedMnemonic && wss.fHDPlainPassphrase);
+    const bool plaintextInEncryptedWallet =
+        wss.fIsEncrypted &&
+        (wss.nKeys != 0 || wss.fHDPlainMnemonic || wss.fHDPlainPassphrase);
+    const bool encryptedHDInPlainWallet =
+        !wss.fIsEncrypted &&
+        (wss.fHDCryptedMnemonic || wss.fHDCryptedPassphrase);
+    const bool encryptedKeysWithoutMasterKey =
+        wss.nCKeys != 0 && pwallet->mapMasterKeys.empty();
+
+    if (conflictingMnemonicRecords || conflictingPassphraseRecords ||
+        missingMnemonic || mixedHDProtection || plaintextInEncryptedWallet ||
+        encryptedHDInPlainWallet || encryptedKeysWithoutMasterKey) {
+        printf("Error reading wallet database: inconsistent encryption or HD seed records\n");
+        return DB_CORRUPT;
+    }
+
     if (result != DB_LOAD_OK)
         return result;
 
@@ -617,18 +680,55 @@ bool BackupWallet(const CWallet& wallet, const std::string& strDest)
     if (!wallet.fFileBacked)
         return false;
 
-    // For the SQLite backend, the database is a single file — copy directly
-    // (after a checkpoint flush to fold any -wal into the main file).
+    // SQLite's online backup API takes a consistent snapshot while the daemon
+    // is running; copying the live database file directly can produce a torn
+    // backup if a transaction commits during the copy.
     if (ResolveWalletDbKind() == WalletDbKind::SQLite) {
         fs::path pathSrc = GetDataDir() / wallet.strWalletFile;
         fs::path pathDest(strDest);
         if (fs::is_directory(pathDest))
             pathDest /= wallet.strWalletFile;
+
         std::error_code ec;
-        fs::copy_file(pathSrc, pathDest, fs::copy_options::overwrite_existing, ec);
+        if (fs::exists(pathDest, ec) && fs::equivalent(pathSrc, pathDest, ec)) {
+            printf("refusing to back up wallet.dat onto itself\n");
+            return false;
+        }
+        ec.clear();
+
+        const fs::path pathTemp = pathDest.string() +
+            strprintf(".tmp.%" PRId64, GetTimeMillis());
+        try {
+            CWalletDB walletdb(wallet.strWalletFile);
+            if (!walletdb.BackupDatabase(pathTemp.string())) {
+                fs::remove(pathTemp, ec);
+                return false;
+            }
+        } catch (const std::exception& e) {
+            printf("error backing up wallet.dat to %s - %s\n",
+                   pathDest.string().c_str(), e.what());
+            fs::remove(pathTemp, ec);
+            return false;
+        }
+        if (!RestrictWalletFilePermissions(pathTemp)) {
+            printf("error restricting wallet backup permissions: %s\n",
+                   pathDest.string().c_str());
+            fs::remove(pathTemp, ec);
+            return false;
+        }
+        fs::rename(pathTemp, pathDest, ec);
+#ifdef WIN32
         if (ec) {
-            printf("error copying wallet.dat to %s - %s\n",
+            ec.clear();
+            fs::remove(pathDest, ec);
+            ec.clear();
+            fs::rename(pathTemp, pathDest, ec);
+        }
+#endif
+        if (ec) {
+            printf("error finalizing wallet backup %s - %s\n",
                    pathDest.string().c_str(), ec.message().c_str());
+            fs::remove(pathTemp, ec);
             return false;
         }
         printf("copied wallet.dat to %s\n", pathDest.string().c_str());
@@ -653,6 +753,11 @@ bool BackupWallet(const CWallet& wallet, const std::string& strDest)
 
                 try {
                     fs::copy_file(pathSrc, pathDest, fs::copy_options::overwrite_existing);
+                    if (!RestrictWalletFilePermissions(pathDest)) {
+                        printf("error restricting wallet backup permissions: %s\n",
+                               pathDest.string().c_str());
+                        return false;
+                    }
                     printf("copied wallet.dat to %s\n", pathDest.string().c_str());
                     return true;
                 } catch (const fs::filesystem_error& e) {
@@ -665,4 +770,4 @@ bool BackupWallet(const CWallet& wallet, const std::string& strDest)
         MilliSleep(100);
     }
     return false;
-}
\ No newline at end of file
+}
diff --git a/src/walletdb.h b/src/walletdb.h
index 07ccce4..c9be309 100644
--- a/src/walletdb.h
+++ b/src/walletdb.h
@@ -123,8 +123,10 @@ public:
             return false;
         if (fEraseUnencryptedKey)
         {
-            Erase(std::make_pair(std::string("key"), vchPubKey.Raw()));
-            Erase(std::make_pair(std::string("wkey"), vchPubKey.Raw()));
+            if (!Erase(std::make_pair(std::string("key"), vchPubKey.Raw())))
+                return false;
+            if (!Erase(std::make_pair(std::string("wkey"), vchPubKey.Raw())))
+                return false;
         }
         return true;
     }
@@ -166,13 +168,13 @@ public:
 
     bool WriteHDMnemonic(const std::string& mnemonic) {
         nWalletDBUpdated++;
-        Erase(std::string("hdcmnemonic"));
-        return Write(std::string("hdmnemonic"), mnemonic);
+        const bool erased = Erase(std::string("hdcmnemonic"));
+        return erased && Write(std::string("hdmnemonic"), mnemonic);
     }
     bool WriteHDCryptedMnemonic(const uint256& iv, const std::vector<unsigned char>& cipher) {
         nWalletDBUpdated++;
-        Erase(std::string("hdmnemonic"));
-        return Write(std::string("hdcmnemonic"), std::make_pair(iv, cipher));
+        const bool erased = Erase(std::string("hdmnemonic"));
+        return erased && Write(std::string("hdcmnemonic"), std::make_pair(iv, cipher));
     }
     bool WriteHDChain(int64_t nIndex) {
         nWalletDBUpdated++;
@@ -183,19 +185,19 @@ public:
     // means no passphrase (legacy wallets and the common case).
     bool WriteHDPassphrase(const std::string& passphrase) {
         nWalletDBUpdated++;
-        Erase(std::string("hdcpassphrase"));
-        return Write(std::string("hdpassphrase"), passphrase);
+        const bool erased = Erase(std::string("hdcpassphrase"));
+        return erased && Write(std::string("hdpassphrase"), passphrase);
     }
     bool WriteHDCryptedPassphrase(const uint256& iv, const std::vector<unsigned char>& cipher) {
         nWalletDBUpdated++;
-        Erase(std::string("hdpassphrase"));
-        return Write(std::string("hdcpassphrase"), std::make_pair(iv, cipher));
+        const bool erased = Erase(std::string("hdpassphrase"));
+        return erased && Write(std::string("hdcpassphrase"), std::make_pair(iv, cipher));
     }
     bool EraseHDPassphrase() {
         nWalletDBUpdated++;
-        Erase(std::string("hdpassphrase"));
-        Erase(std::string("hdcpassphrase"));
-        return true;
+        const bool erasedPlain = Erase(std::string("hdpassphrase"));
+        const bool erasedCrypted = Erase(std::string("hdcpassphrase"));
+        return erasedPlain && erasedCrypted;
     }
 
     bool ReadPool(int64_t nPool, CKeyPool& keypool)
@@ -251,6 +253,16 @@ public:
         return Read(std::string("version"), nVersion);
     }
 
+    bool RewriteDatabase(const char* pszSkip = nullptr)
+    {
+        return m_database && m_database->Rewrite(pszSkip);
+    }
+
+    bool BackupDatabase(const std::string& destination) const
+    {
+        return m_database && m_database->Backup(destination);
+    }
+
     bool ReadAccount(const std::string& strAccount, CAccount& account);
     bool WriteAccount(const std::string& strAccount, const CAccount& account);
 private: