diff --git a/.github/workflows/build-and-test.yml b/.github/workflows/build-and-test.yml
index 9d9132a2ca623..30dab77a2a7ec 100644
--- a/.github/workflows/build-and-test.yml
+++ b/.github/workflows/build-and-test.yml
@@ -73,13 +73,13 @@ jobs:
         config:
           - name: Linux
             os: ubuntu-18.04
-            packages: python3-zmq qttools5-dev qtbase5-dev qttools5-dev-tools libqt5svg5-dev libqt5charts5-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-test-dev libboost-thread-dev libdb5.3++-dev libminiupnpc-dev libzmq3-dev libqrencode-dev libgmp-dev libsodium-dev cargo
+            packages: python3-zmq qttools5-dev qtbase5-dev qttools5-dev-tools libqt5svg5-dev libqt5charts5-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-test-dev libboost-thread-dev libdb5.3++-dev libminiupnpc-dev libzmq3-dev libqrencode-dev libgmp-dev cargo
             cc: gcc
             cxx: g++
 
           - name: macOS
             os: macos-10.15
-            packages: python3 autoconf automake berkeley-db4 libtool boost miniupnpc libnatpmp pkg-config qt5 zmq libevent qrencode gmp libsodium rust
+            packages: python3 autoconf automake berkeley-db4 libtool boost miniupnpc libnatpmp pkg-config qt5 zmq libevent qrencode gmp rust
             cc: $(brew --prefix llvm)/bin/clang
             cxx: $(brew --prefix llvm)/bin/clang++
 
@@ -93,11 +93,17 @@ jobs:
             sudo apt-add-repository "ppa:ondrej/php" -y
             sudo apt-get --yes update
             sudo apt-get install --no-install-recommends --no-upgrade -qq "$APT_BASE" ${{ matrix.config.packages }}
+            sudo dpkg --remove --force-depends libsodium-dev
           fi
           if [[ ${{ matrix.config.os }} = macos* ]]; then
             brew install "$APT_BASE" ${{ matrix.config.packages }}
+            brew uninstall --ignore-dependencies libsodium
           fi
 
+          echo "Installing libsodium.."
+          sudo ./contrib/install_sodium.sh `pwd`
+          echo "libsodium install finished.."
+
       - name: Prepare ccache timestamp
         id: ccache_cache_timestamp
         shell: cmake -P {0}
@@ -118,8 +124,8 @@ jobs:
           CC=${{ matrix.config.cc }}
           CXX=${{ matrix.config.cxx }}
           if [[ ${{ matrix.config.os }} = macos* ]]; then
-            export CPPFLAGS="-I/usr/local/Cellar/gmp/6.2.1/include"
-            export LDFLAGS="-L/usr/local/Cellar/gmp/6.2.1/lib"
+            export CPPFLAGS="-I/usr/local/Cellar/gmp/6.2.1/include -I/usr/local/include"
+            export LDFLAGS="-L/usr/local/Cellar/gmp/6.2.1/lib -L/usr/local/lib"
           fi
           export CC
           export CXX
@@ -303,7 +309,16 @@ jobs:
           - name: x86_64 Linux  [GOAL:install]  [bionic]  [no depends only system libs]
             os: ubuntu-18.04
             host: x86_64-unknown-linux-gnu
-            apt_get: python3-zmq qtbase5-dev qttools5-dev-tools libqt5svg5-dev libqt5charts5-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-test-dev libboost-thread-dev libdb5.3++-dev libminiupnpc-dev libnatpmp-dev libzmq3-dev libqrencode-dev libgmp-dev libsodium-dev cargo
+            apt_get: python3-zmq qtbase5-dev qttools5-dev-tools libqt5svg5-dev libqt5charts5-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-test-dev libboost-thread-dev libdb5.3++-dev libminiupnpc-dev libnatpmp-dev libzmq3-dev libqrencode-dev libgmp-dev cargo
+            unit_tests: true
+            no_depends: 1
+            goal: install
+            BITCOIN_CONFIG: "--enable-zmq --with-incompatible-bdb --with-gui=qt5 CPPFLAGS=-DDEBUG_LOCKORDER"
+
+          - name: x86_64 Linux  [GOAL:install]  [focal]  [no depends only system libs]
+            os: ubuntu-20.04
+            host: x86_64-unknown-linux-gnu
+            apt_get: python3-zmq qtbase5-dev qttools5-dev-tools libqt5svg5-dev libqt5charts5-dev libevent-dev bsdmainutils libboost-system-dev libboost-filesystem-dev libboost-chrono-dev libboost-test-dev libboost-thread-dev libdb5.3++-dev libminiupnpc-dev libsodium1.0.17-dev libzmq3-dev libqrencode-dev libgmp-dev cargo
             unit_tests: true
             no_depends: 1
             goal: install
@@ -323,7 +338,7 @@ jobs:
           - name: macOS 10.15 [GOAL:deploy] [native macOS using syslibs no unit or functional tests]
             os: macos-10.15
             host: x86_64-apple-darwin19.6.0
-            brew_install: autoconf automake ccache berkeley-db4 libtool boost miniupnpc pkg-config python3 qt5 zmq libevent qrencode gmp libsodium rust librsvg
+            brew_install: autoconf automake ccache berkeley-db4 libtool boost miniupnpc pkg-config python3 qt5 zmq libevent qrencode gmp rust librsvg
             unit_tests: false
             functional_tests: false
             no_depends: 1
@@ -340,6 +355,7 @@ jobs:
         run: |
           if [[ ${{ matrix.config.os }} = ubuntu* ]]; then
             sudo apt-add-repository "ppa:ondrej/php" -y
+            sudo apt-add-repository "ppa:fuzzbawls/libsodium1.0.17" -y
             sudo apt-get --yes update
             sudo apt-get install --no-install-recommends --no-upgrade -qq "$APT_BASE" ${{ matrix.config.apt_get }}
           fi
@@ -348,6 +364,21 @@ jobs:
             pip3 install ds_store mac_alias
           fi
 
+          if [ "${{ matrix.config.no_depends }}" = 1 ]; then
+            if [ "${{ matrix.config.os }}" != "ubuntu-20.04" ] && "${{ matrix.config.os }}" != "macos-10.15" ]; then
+                sudo dpkg --remove --force-depends libsodium-dev
+            fi
+
+            if [[ ${{ matrix.config.os }} = macos* ]]; then
+                brew install "$APT_BASE" ${{ matrix.config.packages }}
+                brew uninstall --ignore-dependencies libsodium
+            fi
+
+            echo "Installing libsodium.."
+            sudo ./contrib/install_sodium.sh `pwd`
+            echo "libsodium install finished.."
+          fi
+
       - name: depends cache files
         if: matrix.config.no_depends != 1
         uses: actions/cache@v2
diff --git a/CMakeLists.txt b/CMakeLists.txt
index cff73d1a9638f..1746bc0648977 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -409,6 +409,7 @@ set(UTIL_SOURCES
         ./src/compat/strnlen.cpp
         ./src/compat/glibc_sanity.cpp
         ./src/compat/glibcxx_sanity.cpp
+        ./src/sapling/sodium_sanity.cpp
         ./src/chainparamsbase.cpp
         ./src/clientversion.cpp
         ./src/fs.cpp
diff --git a/configure.ac b/configure.ac
index 7456cb67df48a..f5c194fcba53b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1166,7 +1166,7 @@ if test x$use_pkgconfig = xyes; then
         if test x$TARGET_OS != xwindows; then
           PKG_CHECK_MODULES([EVENT_PTHREADS], [libevent_pthreads],, [AC_MSG_ERROR(libevent_pthreads not found.)])
         fi
-        PKG_CHECK_MODULES([SODIUM], [libsodium],, [AC_MSG_ERROR(libsodium not found.)])
+        PKG_CHECK_MODULES([SODIUM], [libsodium], [have_sodium=yes], [AC_MSG_ERROR(libsodium not found.)])
       fi
 
       if test "x$use_zmq" = "xyes"; then
@@ -1188,7 +1188,7 @@ else
     if test x$TARGET_OS != xwindows; then
       AC_CHECK_LIB([event_pthreads],[main],EVENT_PTHREADS_LIBS=-levent_pthreads,AC_MSG_ERROR(libevent_pthreads missing))
     fi
-    AC_CHECK_HEADER([sodium/core.h],, AC_MSG_ERROR(libsodium headers missing),)
+    AC_CHECK_HEADER([sodium/core.h], [have_sodium=yes], AC_MSG_ERROR(libsodium headers missing),)
     AC_CHECK_LIB([sodium],[main],SODIUM_LIBS=-lsodium,AC_MSG_ERROR(libsodium missing))
   fi
 
@@ -1223,6 +1223,31 @@ else
   fi
 fi
 
+dnl check for supported sodium library version
+if test x$have_sodium != xno; then
+  AC_MSG_CHECKING([whether libsodium library version is supported])
+  AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[
+      #include <sodium.h>
+    ]], [[
+      #if SODIUM_LIBRARY_VERSION_MAJOR <= 10
+      // Everything is okay
+      #elif SODIUM_LIBRARY_VERSION_MAJOR == 10
+        #if SODIUM_LIBRARY_VERSION_MINOR == 0
+        // Everything is okay
+        #else
+        #  error libsodium library minor version is unsupported
+        #endif
+      #else
+      #  error libsodium library major version is unsupported
+      #endif
+    ]])],[
+      AC_MSG_RESULT(yes)
+    ],[
+    AC_MSG_RESULT(no)
+    AC_MSG_ERROR([libsodium library version > 10.1 is unsupported.])
+  ])
+fi
+
 dnl gmp check
 GMP_CHECK
 if test x"$has_gmp" != x"yes"; then
diff --git a/contrib/cmake/FindSodium.cmake b/contrib/cmake/FindSodium.cmake
index b38c994e34a7b..918f8ee0f6df4 100644
--- a/contrib/cmake/FindSodium.cmake
+++ b/contrib/cmake/FindSodium.cmake
@@ -86,123 +86,6 @@ if (UNIX)
     find_library(sodium_LIBRARY_RELEASE NAMES ${${XPREFIX}_LIBRARIES}
             HINTS ${${XPREFIX}_LIBRARY_DIRS}
             )
-
-
-    ########################################################################
-    # Windows
-elseif (WIN32)
-    set(sodium_DIR "$ENV{sodium_DIR}" CACHE FILEPATH "sodium install directory")
-    mark_as_advanced(sodium_DIR)
-
-    find_path(sodium_INCLUDE_DIR sodium.h
-            HINTS ${sodium_DIR}
-            PATH_SUFFIXES include
-            )
-
-    if (MSVC)
-        # detect target architecture
-        file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/arch.cpp" [=[
-            #if defined _M_IX86
-            #error ARCH_VALUE x86_32
-            #elif defined _M_X64
-            #error ARCH_VALUE x86_64
-            #endif
-            #error ARCH_VALUE unknown
-        ]=])
-        try_compile(_UNUSED_VAR "${CMAKE_CURRENT_BINARY_DIR}" "${CMAKE_CURRENT_BINARY_DIR}/arch.cpp"
-                OUTPUT_VARIABLE _COMPILATION_LOG
-                )
-        string(REGEX REPLACE ".*ARCH_VALUE ([a-zA-Z0-9_]+).*" "\\1" _TARGET_ARCH "${_COMPILATION_LOG}")
-
-        # construct library path
-        if (_TARGET_ARCH STREQUAL "x86_32")
-            string(APPEND _PLATFORM_PATH "Win32")
-        elseif(_TARGET_ARCH STREQUAL "x86_64")
-            string(APPEND _PLATFORM_PATH "x64")
-        else()
-            message(FATAL_ERROR "the ${_TARGET_ARCH} architecture is not supported by Findsodium.cmake.")
-        endif()
-        string(APPEND _PLATFORM_PATH "/$$CONFIG$$")
-
-        if (MSVC_VERSION LESS 1900)
-            math(EXPR _VS_VERSION "${MSVC_VERSION} / 10 - 60")
-        else()
-            math(EXPR _VS_VERSION "${MSVC_VERSION} / 10 - 50")
-        endif()
-        string(APPEND _PLATFORM_PATH "/v${_VS_VERSION}")
-
-        if (sodium_USE_STATIC_LIBS)
-            string(APPEND _PLATFORM_PATH "/static")
-        else()
-            string(APPEND _PLATFORM_PATH "/dynamic")
-        endif()
-
-        string(REPLACE "$$CONFIG$$" "Debug" _DEBUG_PATH_SUFFIX "${_PLATFORM_PATH}")
-        string(REPLACE "$$CONFIG$$" "Release" _RELEASE_PATH_SUFFIX "${_PLATFORM_PATH}")
-
-        find_library(sodium_LIBRARY_DEBUG libsodium.lib
-                HINTS ${sodium_DIR}
-                PATH_SUFFIXES ${_DEBUG_PATH_SUFFIX}
-                )
-        find_library(sodium_LIBRARY_RELEASE libsodium.lib
-                HINTS ${sodium_DIR}
-                PATH_SUFFIXES ${_RELEASE_PATH_SUFFIX}
-                )
-        if (NOT sodium_USE_STATIC_LIBS)
-            set(CMAKE_FIND_LIBRARY_SUFFIXES_BCK ${CMAKE_FIND_LIBRARY_SUFFIXES})
-            set(CMAKE_FIND_LIBRARY_SUFFIXES ".dll")
-            find_library(sodium_DLL_DEBUG libsodium
-                    HINTS ${sodium_DIR}
-                    PATH_SUFFIXES ${_DEBUG_PATH_SUFFIX}
-                    )
-            find_library(sodium_DLL_RELEASE libsodium
-                    HINTS ${sodium_DIR}
-                    PATH_SUFFIXES ${_RELEASE_PATH_SUFFIX}
-                    )
-            set(CMAKE_FIND_LIBRARY_SUFFIXES ${CMAKE_FIND_LIBRARY_SUFFIXES_BCK})
-        endif()
-
-    elseif(_GCC_COMPATIBLE)
-        if (sodium_USE_STATIC_LIBS)
-            find_library(sodium_LIBRARY_DEBUG libsodium.a
-                    HINTS ${sodium_DIR}
-                    PATH_SUFFIXES lib
-                    )
-            find_library(sodium_LIBRARY_RELEASE libsodium.a
-                    HINTS ${sodium_DIR}
-                    PATH_SUFFIXES lib
-                    )
-        else()
-            find_library(sodium_LIBRARY_DEBUG libsodium.dll.a
-                    HINTS ${sodium_DIR}
-                    PATH_SUFFIXES lib
-                    )
-            find_library(sodium_LIBRARY_RELEASE libsodium.dll.a
-                    HINTS ${sodium_DIR}
-                    PATH_SUFFIXES lib
-                    )
-
-            file(GLOB _DLL
-                    LIST_DIRECTORIES false
-                    RELATIVE "${sodium_DIR}/bin"
-                    "${sodium_DIR}/bin/libsodium*.dll"
-                    )
-            find_library(sodium_DLL_DEBUG ${_DLL} libsodium
-                    HINTS ${sodium_DIR}
-                    PATH_SUFFIXES bin
-                    )
-            find_library(sodium_DLL_RELEASE ${_DLL} libsodium
-                    HINTS ${sodium_DIR}
-                    PATH_SUFFIXES bin
-                    )
-        endif()
-    else()
-        message(FATAL_ERROR "this platform is not supported by FindSodium.cmake")
-    endif()
-
-
-    ########################################################################
-    # unsupported
 else()
     message(FATAL_ERROR "this platform is not supported by FindSodium.cmake")
 endif()
@@ -213,12 +96,25 @@ endif()
 
 # extract sodium version
 if (sodium_INCLUDE_DIR)
-    set(_VERSION_HEADER "${_INCLUDE_DIR}/sodium/version.h")
-    if (EXISTS _VERSION_HEADER)
+    set(_VERSION_HEADER "${sodium_INCLUDE_DIR}/sodium/version.h")
+    if (EXISTS "${_VERSION_HEADER}")
         file(READ "${_VERSION_HEADER}" _VERSION_HEADER_CONTENT)
         string(REGEX REPLACE ".*#[ \t]*define[ \t]*SODIUM_VERSION_STRING[ \t]*\"([^\n]*)\".*" "\\1"
                 sodium_VERSION "${_VERSION_HEADER_CONTENT}")
-        set(sodium_VERSION "${sodium_VERSION}" PARENT_SCOPE)
+        set(sodium_VERSION "${sodium_VERSION}")
+        message(STATUS "Found libsodium version ${sodium_VERSION}")
+
+        # extract the sodium library version
+        string(REGEX REPLACE ".*#[ \t]*define[ \t]*SODIUM_LIBRARY_VERSION_MAJOR[ \t]*([^\n]*).*" "\\1"
+                sodium_LIBRARY_VERSION_MAJOR "${_VERSION_HEADER_CONTENT}")
+        string(REGEX REPLACE ".*#[ \t]*define[ \t]*SODIUM_LIBRARY_VERSION_MINOR[ \t]*([^\n]*).*" "\\1"
+                sodium_LIBRARY_VERSION_MINOR "${_VERSION_HEADER_CONTENT}")
+        set(sodium_LIBRARY_VERSION "${sodium_LIBRARY_VERSION_MAJOR}.${sodium_LIBRARY_VERSION_MINOR}")
+        message(STATUS "libsodium library version found: ${sodium_LIBRARY_VERSION}")
+        if (${sodium_LIBRARY_VERSION} VERSION_GREATER "10.0")
+            message(FATAL_ERROR "Unsupported libsodium library version ${sodium_LIBRARY_VERSION}!")
+        endif()
+
     endif()
 endif()
 
@@ -243,10 +139,6 @@ endif()
 mark_as_advanced(sodium_INCLUDE_DIR)
 mark_as_advanced(sodium_LIBRARY_DEBUG)
 mark_as_advanced(sodium_LIBRARY_RELEASE)
-if (WIN32)
-    mark_as_advanced(sodium_DLL_DEBUG)
-    mark_as_advanced(sodium_DLL_RELEASE)
-endif()
 
 # create imported target
 if(sodium_USE_STATIC_LIBS)
@@ -273,22 +165,5 @@ else()
                 IMPORTED_LOCATION "${sodium_LIBRARY_RELEASE}"
                 IMPORTED_LOCATION_DEBUG "${sodium_LIBRARY_DEBUG}"
                 )
-    elseif (WIN32)
-        set_target_properties(sodium PROPERTIES
-                IMPORTED_IMPLIB "${sodium_LIBRARY_RELEASE}"
-                IMPORTED_IMPLIB_DEBUG "${sodium_LIBRARY_DEBUG}"
-                )
-        if (NOT (sodium_DLL_DEBUG MATCHES ".*-NOTFOUND"))
-            set_target_properties(sodium PROPERTIES
-                    IMPORTED_LOCATION_DEBUG "${sodium_DLL_DEBUG}"
-                    )
-        endif()
-        if (NOT (sodium_DLL_RELEASE MATCHES ".*-NOTFOUND"))
-            set_target_properties(sodium PROPERTIES
-                    IMPORTED_LOCATION_RELWITHDEBINFO "${sodium_DLL_RELEASE}"
-                    IMPORTED_LOCATION_MINSIZEREL "${sodium_DLL_RELEASE}"
-                    IMPORTED_LOCATION_RELEASE "${sodium_DLL_RELEASE}"
-                    )
-        endif()
     endif()
 endif()
\ No newline at end of file
diff --git a/contrib/install_sodium.sh b/contrib/install_sodium.sh
new file mode 100755
index 0000000000000..800bc635a892a
--- /dev/null
+++ b/contrib/install_sodium.sh
@@ -0,0 +1,85 @@
+#!/bin/sh
+
+# Install patched libsodium 1.0.17.
+
+export LC_ALL=C
+set -e
+
+if [ -z "${1}" ]; then
+  echo "Usage: $0 <base-dir> [<extra-sodium-configure-flag> ...]"
+  echo
+  echo "Must specify a single argument: the directory in which sodium will be built."
+  echo "This is probably \`pwd\` if you're at the root of the pivx repository."
+  exit 1
+fi
+
+expand_path() {
+  echo "$(cd "${1}" && pwd -P)"
+}
+
+ROOT_PREFIX="$(expand_path ${1})";
+SODIUM_PREFIX="$ROOT_PREFIX/sodium"; shift;
+echo $SODIUM_PREFIX
+echo $ROOT_PREFIX
+SODIUM_VERSION='1.0.17'
+SODIUM_HASH='0cc3dae33e642cc187b5ceb467e0ad0e1b51dcba577de1190e9ffa17766ac2b1'
+SODIUM_URL="https://download.libsodium.org/libsodium/releases/libsodium-${SODIUM_VERSION}.tar.gz"
+
+check_exists() {
+  which "$1" >/dev/null 2>&1
+}
+
+sha256_check() {
+  # Args: <sha256_hash> <filename>
+  #
+  if check_exists sha256sum; then
+    echo "${1}  ${2}" | sha256sum -c
+  elif check_exists sha256; then
+    if [ "$(uname)" = "FreeBSD" ]; then
+      sha256 -c "${1}" "${2}"
+    else
+      echo "${1}  ${2}" | sha256 -c
+    fi
+  else
+    echo "${1}  ${2}" | shasum -a 256 -c
+  fi
+}
+
+http_get() {
+  # Args: <url> <filename> <sha256_hash>
+  #
+  # It's acceptable that we don't require SSL here because we manually verify
+  # content hashes below.
+  #
+  if [ -f "${2}" ]; then
+    echo "File ${2} already exists; not downloading again"
+  elif check_exists curl; then
+    curl --insecure --retry 5 "${1}" -o "${2}"
+  else
+    wget --no-check-certificate "${1}" -O "${2}"
+  fi
+
+  sha256_check "${3}" "${2}"
+}
+
+mkdir -p "${SODIUM_PREFIX}"
+http_get "${SODIUM_URL}" "libsodium-${SODIUM_VERSION}.tar.gz" "${SODIUM_HASH}"
+tar -xzvf libsodium-${SODIUM_VERSION}.tar.gz -C "$SODIUM_PREFIX"
+cd "${SODIUM_PREFIX}/libsodium-${SODIUM_VERSION}/"
+
+# Apply patches
+echo "Applying patches.."
+patch -p1 < "${ROOT_PREFIX}/depends/patches/libsodium/1.0.15-pubkey-validation.diff" && \
+patch -p1 < "${ROOT_PREFIX}/depends/patches/libsodium/1.0.15-signature-validation.diff" && \
+patch -p1 < "${ROOT_PREFIX}/depends/patches/libsodium/1.0.15-library-version.diff" && \
+DO_NOT_UPDATE_CONFIG_SCRIPTS=1 ./autogen.sh
+
+# make
+"${SODIUM_PREFIX}/libsodium-${SODIUM_VERSION}/configure" --enable-static --disable-shared
+make && make check
+
+make install
+
+echo
+echo "sodium build complete."
+echo
diff --git a/depends/packages/libsodium.mk b/depends/packages/libsodium.mk
index 173a4f0d0eb8c..4a45a68bdad5c 100644
--- a/depends/packages/libsodium.mk
+++ b/depends/packages/libsodium.mk
@@ -1,13 +1,17 @@
 package=libsodium
-$(package)_version=1.0.15
-$(package)_download_path=https://download.libsodium.org/libsodium/releases/old/unsupported/
+$(package)_version=1.0.17
+$(package)_download_path=https://download.libsodium.org/libsodium/releases/
 $(package)_file_name=$(package)-$($(package)_version).tar.gz
-$(package)_sha256_hash=fb6a9e879a2f674592e4328c5d9f79f082405ee4bb05cb6e679b90afe9e178f4
+$(package)_sha256_hash=0cc3dae33e642cc187b5ceb467e0ad0e1b51dcba577de1190e9ffa17766ac2b1
 $(package)_dependencies=
+$(package)_patches=1.0.15-pubkey-validation.diff 1.0.15-signature-validation.diff 1.0.15-library-version.diff
 $(package)_config_opts=
 
 define $(package)_preprocess_cmds
-  cd $($(package)_build_subdir); ./autogen.sh
+  patch -p1 < $($(package)_patch_dir)/1.0.15-pubkey-validation.diff && \
+  patch -p1 < $($(package)_patch_dir)/1.0.15-signature-validation.diff && \
+  patch -p1 < $($(package)_patch_dir)/1.0.15-library-version.diff && \
+  cd $($(package)_build_subdir); DO_NOT_UPDATE_CONFIG_SCRIPTS=1 ./autogen.sh
 endef
 
 define $(package)_config_cmds
diff --git a/depends/patches/libsodium/1.0.15-library-version.diff b/depends/patches/libsodium/1.0.15-library-version.diff
new file mode 100644
index 0000000000000..18455776311f3
--- /dev/null
+++ b/depends/patches/libsodium/1.0.15-library-version.diff
@@ -0,0 +1,12 @@
+diff -ur libsodium-1.0.17-orig/configure.ac libsodium-1.0.17/configure.ac
+--- libsodium-1.0.17-orig/configure.ac	2019-01-06 12:29:47.000000000 -0800
++++ libsodium-1.0.17/configure.ac	2021-05-17 18:22:25.582171400 -0700
+@@ -15,7 +15,7 @@
+ AC_SUBST(VERSION)
+ 
+ SODIUM_LIBRARY_VERSION_MAJOR=10
+-SODIUM_LIBRARY_VERSION_MINOR=2
++SODIUM_LIBRARY_VERSION_MINOR=0
+ DLL_VERSION=23
+ SODIUM_LIBRARY_VERSION=25:0:2
+ #                       | | |
diff --git a/depends/patches/libsodium/1.0.15-pubkey-validation.diff b/depends/patches/libsodium/1.0.15-pubkey-validation.diff
new file mode 100644
index 0000000000000..e516d1025671e
--- /dev/null
+++ b/depends/patches/libsodium/1.0.15-pubkey-validation.diff
@@ -0,0 +1,17 @@
+diff -ur libsodium-1.0.17-orig/src/libsodium/crypto_sign/ed25519/ref10/open.c libsodium-1.0.17/src/libsodium/crypto_sign/ed25519/ref10/open.c
+--- libsodium-1.0.17-orig/src/libsodium/crypto_sign/ed25519/ref10/open.c	2019-05-18 16:32:11.000000000 -0400
++++ libsodium-1.0.17/src/libsodium/crypto_sign/ed25519/ref10/open.c	2020-01-21 18:55:22.474233831 -0500
+@@ -32,8 +32,11 @@
+         ge25519_has_small_order(sig) != 0) {
+         return -1;
+     }
+-    if (ge25519_is_canonical(pk) == 0 ||
+-        ge25519_has_small_order(pk) != 0) {
++    unsigned char d = 0;
++    for (int i = 0; i < 32; ++i) {
++        d |= pk[i];
++    }
++    if (d == 0) {
+         return -1;
+     }
+ #endif
diff --git a/depends/patches/libsodium/1.0.15-signature-validation.diff b/depends/patches/libsodium/1.0.15-signature-validation.diff
new file mode 100644
index 0000000000000..dc9522f17918c
--- /dev/null
+++ b/depends/patches/libsodium/1.0.15-signature-validation.diff
@@ -0,0 +1,94 @@
+diff -ur libsodium-1.0.17-orig/src/libsodium/crypto_sign/ed25519/ref10/open.c libsodium-1.0.17/src/libsodium/crypto_sign/ed25519/ref10/open.c
+--- libsodium-1.0.17-orig/src/libsodium/crypto_sign/ed25519/ref10/open.c	2019-05-18 21:32:11.000000000 +0100
++++ libsodium-1.0.17/src/libsodium/crypto_sign/ed25519/ref10/open.c	2020-02-18 00:00:08.544107613 +0000
+@@ -10,6 +10,81 @@
+ #include "private/ed25519_ref10.h"
+ #include "utils.h"
+ 
++#ifndef ED25519_COMPAT
++int
++_crypto_sign_ed25519_small_order(const unsigned char p[32])
++{
++    CRYPTO_ALIGN(16)
++    static const unsigned char blacklist[][32] = {
++        /* 0 (order 4) */
++        { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
++          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
++          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
++        /* 1 (order 1) */
++        { 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
++          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
++          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
++        /* 2707385501144840649318225287225658788936804267575313519463743609750303402022
++           (order 8) */
++        { 0x26, 0xe8, 0x95, 0x8f, 0xc2, 0xb2, 0x27, 0xb0, 0x45, 0xc3, 0xf4,
++          0x89, 0xf2, 0xef, 0x98, 0xf0, 0xd5, 0xdf, 0xac, 0x05, 0xd3, 0xc6,
++          0x33, 0x39, 0xb1, 0x38, 0x02, 0x88, 0x6d, 0x53, 0xfc, 0x05 },
++        /* 55188659117513257062467267217118295137698188065244968500265048394206261417927
++           (order 8) */
++        { 0xc7, 0x17, 0x6a, 0x70, 0x3d, 0x4d, 0xd8, 0x4f, 0xba, 0x3c, 0x0b,
++          0x76, 0x0d, 0x10, 0x67, 0x0f, 0x2a, 0x20, 0x53, 0xfa, 0x2c, 0x39,
++          0xcc, 0xc6, 0x4e, 0xc7, 0xfd, 0x77, 0x92, 0xac, 0x03, 0x7a },
++        /* p-1 (order 2) */
++        { 0x13, 0xe8, 0x95, 0x8f, 0xc2, 0xb2, 0x27, 0xb0, 0x45, 0xc3, 0xf4,
++          0x89, 0xf2, 0xef, 0x98, 0xf0, 0xd5, 0xdf, 0xac, 0x05, 0xd3, 0xc6,
++          0x33, 0x39, 0xb1, 0x38, 0x02, 0x88, 0x6d, 0x53, 0xfc, 0x85 },
++        /* p (order 4) */
++        { 0xb4, 0x17, 0x6a, 0x70, 0x3d, 0x4d, 0xd8, 0x4f, 0xba, 0x3c, 0x0b,
++          0x76, 0x0d, 0x10, 0x67, 0x0f, 0x2a, 0x20, 0x53, 0xfa, 0x2c, 0x39,
++          0xcc, 0xc6, 0x4e, 0xc7, 0xfd, 0x77, 0x92, 0xac, 0x03, 0xfa },
++        /* p+1 (order 1) */
++        { 0xec, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
++        /* p+2707385501144840649318225287225658788936804267575313519463743609750303402022
++           (order 8) */
++        { 0xed, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
++        /* p+55188659117513257062467267217118295137698188065244968500265048394206261417927
++           (order 8) */
++        { 0xee, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f },
++        /* 2p-1 (order 2) */
++        { 0xd9, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
++        /* 2p (order 4) */
++        { 0xda, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
++        /* 2p+1 (order 1) */
++        { 0xdb, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
++          0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }
++    };
++    size_t        i, j;
++    unsigned char c;
++
++    for (i = 0; i < sizeof blacklist / sizeof blacklist[0]; i++) {
++        c = 0;
++        for (j = 0; j < 32; j++) {
++            c |= p[j] ^ blacklist[i][j];
++        }
++        if (c == 0) {
++            return 1;
++        }
++    }
++    return 0;
++}
++#endif
++
+ int
+ _crypto_sign_ed25519_verify_detached(const unsigned char *sig,
+                                      const unsigned char *m,
+@@ -29,7 +104,7 @@
+     }
+ #else
+     if (sc25519_is_canonical(sig + 32) == 0 ||
+-        ge25519_has_small_order(sig) != 0) {
++        _crypto_sign_ed25519_small_order(sig) != 0) {
+         return -1;
+     }
+     if (ge25519_is_canonical(pk) == 0 ||
diff --git a/src/Makefile.am b/src/Makefile.am
index 08ced54a504e1..fc60274a6e8a5 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -168,6 +168,7 @@ BITCOIN_CORE_H = \
   compat/cpuid.h \
   compat/endian.h \
   compat/sanity.h \
+  sapling/sodium_sanity.h \
   compressor.h \
   consensus/consensus.h \
   consensus/merkle.h \
@@ -545,6 +546,7 @@ libbitcoin_util_a_SOURCES = \
   clientversion.cpp \
   compat/glibc_sanity.cpp \
   compat/glibcxx_sanity.cpp \
+  sapling/sodium_sanity.cpp \
   compat/strnlen.cpp \
   fs.cpp \
   interfaces/handler.cpp \
diff --git a/src/Makefile.test.include b/src/Makefile.test.include
index 8874296e4d269..755da218fd2ae 100644
--- a/src/Makefile.test.include
+++ b/src/Makefile.test.include
@@ -113,6 +113,7 @@ BITCOIN_TESTS =\
   test/key_tests.cpp \
   test/dbwrapper_tests.cpp \
   test/validation_tests.cpp \
+  test/libsodium_consensus_tests.cpp \
   test/main_tests.cpp \
   test/mempool_tests.cpp \
   test/merkle_tests.cpp \
diff --git a/src/init.cpp b/src/init.cpp
index 8b674186fb7a1..f55a3dc795977 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -41,6 +41,7 @@
 #include "policy/policy.h"
 #include "rpc/register.h"
 #include "rpc/server.h"
+#include "sapling/sodium_sanity.h"
 #include "script/sigcache.h"
 #include "script/standard.h"
 #include "scheduler.h"
@@ -784,6 +785,8 @@ bool InitSanityCheck(void)
         return false;
     }
 
+    libsodium_sanity_test();
+
     return true;
 }
 
@@ -1229,6 +1232,11 @@ bool AppInitSanityChecks()
 {
     // ********************************************************* Step 4: sanity checks
 
+    // Initialize libsodium
+    if (init_and_check_sodium() == -1) {
+        return false;
+    }
+
     // Initialize elliptic curve code
     RandomInit();
     ECC_Start();
diff --git a/src/sapling/sodium_sanity.cpp b/src/sapling/sodium_sanity.cpp
new file mode 100644
index 0000000000000..97cb85d61840e
--- /dev/null
+++ b/src/sapling/sodium_sanity.cpp
@@ -0,0 +1,114 @@
+// Copyright (c) 2020 The Zcash Core developers
+// Copyright (c) 2021 The PIVX Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://www.opensource.org/licenses/mit-license.php.
+
+#include "sodium_sanity.h"
+
+#include "uint256.h"
+#include "utilstrencodings.h"
+
+#include <sodium.h>
+
+int init_and_check_sodium()
+{
+    if (sodium_init() == -1) {
+        return -1;
+    }
+
+    // What follows is a runtime test that ensures the version of libsodium
+    // we're linked against checks that signatures are canonical (s < L).
+    const unsigned char message[1] = { 0 };
+
+    unsigned char pk[crypto_sign_PUBLICKEYBYTES];
+    unsigned char sk[crypto_sign_SECRETKEYBYTES];
+    unsigned char sig[crypto_sign_BYTES];
+
+    crypto_sign_keypair(pk, sk);
+    crypto_sign_detached(sig, NULL, message, sizeof(message), sk);
+
+    assert(crypto_sign_verify_detached(sig, message, sizeof(message), pk) == 0);
+
+    // Copied from libsodium/crypto_sign/ed25519/ref10/open.c
+    static const unsigned char L[32] =
+            { 0xed, 0xd3, 0xf5, 0x5c, 0x1a, 0x63, 0x12, 0x58,
+              0xd6, 0x9c, 0xf7, 0xa2, 0xde, 0xf9, 0xde, 0x14,
+              0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+              0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10 };
+
+    // Add L to S, which starts at sig[32].
+    unsigned int s = 0;
+    for (size_t i = 0; i < 32; i++) {
+        s = sig[32 + i] + L[i] + (s >> 8);
+        sig[32 + i] = s & 0xff;
+    }
+
+    assert(crypto_sign_verify_detached(sig, message, sizeof(message), pk) != 0);
+
+    return 0;
+}
+
+void TestLibsodiumEd25519SignatureVerification(
+        const std::string &scope,
+        const std::string &msg,
+        std::vector<unsigned char> pubkey,
+        std::vector<unsigned char> sig)
+{
+    if (crypto_sign_verify_detached(sig.data(),
+                                    (const unsigned char*)msg.data(),
+                                    msg.size(),
+                                    pubkey.data()) != 0) {
+        throw std::runtime_error("Error, invalid sodium signature verification.\n"
+                                 "The program cannot continue running, not accepted network consensus modifications detected.\n"
+                                 "To solve the issue build the binaries using libsodium 1.0.15 or a patched version of libsodium 1.0.17 (patches available in depends/libsodium)");
+    }
+}
+
+void libsodium_sanity_test()
+{
+    // libsodium <= 1.0.15 accepts valid signatures for a non-zero pubkey with
+    // small order; this is currently part of our consensus rules.
+    // libsodium >= 1.0.16 rejects all pubkeys with small order.
+    //
+    // These test vectors were generated by finding pairs of points (A, P) both
+    // in the eight-torsion subgroup such that R = B + P and R = [1] B - [k] A
+    // (where SHA512(bytes(R) || bytes(A) || message) represents k in
+    // little-endian order, as in Ed25519).
+    TestLibsodiumEd25519SignatureVerification(
+            "Test vector 1",
+            "zcash ed25519 libsodium compatibility",
+            ParseHex("0100000000000000000000000000000000000000000000000000000000000000"),
+            ParseHex("58666666666666666666666666666666666666666666666666666666666666660100000000000000000000000000000000000000000000000000000000000000"));
+    TestLibsodiumEd25519SignatureVerification(
+            "Test vector 2",
+            "zcash ed25519 libsodium compatibility",
+            ParseHex("0000000000000000000000000000000000000000000000000000000000000080"),
+            ParseHex("58666666666666666666666666666666666666666666666666666666666666660100000000000000000000000000000000000000000000000000000000000000"));
+    TestLibsodiumEd25519SignatureVerification(
+            "Test vector 3",
+            "zcash ed25519 libsodium compatibility",
+            ParseHex("26e8958fc2b227b045c3f489f2ef98f0d5dfac05d3c63339b13802886d53fc85"),
+            ParseHex("da99e28ba529cdde35a25fba9059e78ecaee239f99755b9b1aa4f65df00803e20100000000000000000000000000000000000000000000000000000000000000"));
+    TestLibsodiumEd25519SignatureVerification(
+            "Test vector 4",
+            "zcash ed25519 libsodium compatibility",
+            ParseHex("c7176a703d4dd84fba3c0b760d10670f2a2053fa2c39ccc64ec7fd7792ac037a"),
+            ParseHex("95999999999999999999999999999999999999999999999999999999999999990100000000000000000000000000000000000000000000000000000000000000"));
+    TestLibsodiumEd25519SignatureVerification(
+            "Test vector 5",
+            "zcash ed25519 libsodium compatibility",
+            ParseHex("26e8958fc2b227b045c3f489f2ef98f0d5dfac05d3c63339b13802886d53fc85"),
+            ParseHex("13661d745ad63221ca5da0456fa618713511dc60668aa464e55b09a20ff7fc1d0100000000000000000000000000000000000000000000000000000000000000"));
+
+    // libsodium <= 1.0.15 contains a blocklist of small-order points that R is
+    // checked against. However, it does not contain all canonical small-order
+    // points; in particular, it is missing the negative of one of the points.
+    //
+    // This test case is the only pair of points (A, R) both in the eight-torsion
+    // subgroup, that satisfies R = [0] B - [k] A and also evades the blocklist.
+    TestLibsodiumEd25519SignatureVerification(
+            "Small order R that is not rejected by libsodium <= 1.0.15",
+            "zcash ed25519 libsodium compatibility",
+            ParseHex("c7176a703d4dd84fba3c0b760d10670f2a2053fa2c39ccc64ec7fd7792ac037a"),
+            ParseHex("26e8958fc2b227b045c3f489f2ef98f0d5dfac05d3c63339b13802886d53fc850000000000000000000000000000000000000000000000000000000000000000"));
+}
\ No newline at end of file
diff --git a/src/sapling/sodium_sanity.h b/src/sapling/sodium_sanity.h
new file mode 100644
index 0000000000000..cd7b4faa3b62c
--- /dev/null
+++ b/src/sapling/sodium_sanity.h
@@ -0,0 +1,11 @@
+// Copyright (c) 2021 The PIVX Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://www.opensource.org/licenses/mit-license.php.
+
+#ifndef PIVX_SODIUM_SANITY_H
+#define PIVX_SODIUM_SANITY_H
+
+int init_and_check_sodium();
+void libsodium_sanity_test();
+
+#endif //PIVX_SODIUM_SANITY_H
diff --git a/src/test/CMakeLists.txt b/src/test/CMakeLists.txt
index 6be158fdb62e9..237680eedb931 100644
--- a/src/test/CMakeLists.txt
+++ b/src/test/CMakeLists.txt
@@ -102,6 +102,7 @@ set(BITCOIN_TESTS
         ${CMAKE_CURRENT_SOURCE_DIR}/hash_tests.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/key_tests.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/dbwrapper_tests.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/libsodium_consensus_tests.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/main_tests.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/mempool_tests.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/merkle_tests.cpp
diff --git a/src/test/libsodium_consensus_tests.cpp b/src/test/libsodium_consensus_tests.cpp
new file mode 100644
index 0000000000000..2b4fa39e2f4bf
--- /dev/null
+++ b/src/test/libsodium_consensus_tests.cpp
@@ -0,0 +1,16 @@
+// Copyright (c) 2021 The PIVX Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or https://www.opensource.org/licenses/mit-license.php .
+
+#include "test/test_pivx.h"
+#include "sapling/sodium_sanity.h"
+#include <boost/test/unit_test.hpp>
+
+BOOST_FIXTURE_TEST_SUITE(libsodium_consensus_tests, TestingSetup)
+
+BOOST_AUTO_TEST_CASE(LibsodiumPubkeyValidation)
+{
+    libsodium_sanity_test();
+}
+
+BOOST_AUTO_TEST_SUITE_END()
\ No newline at end of file
diff --git a/src/test/test_pivx.cpp b/src/test/test_pivx.cpp
index b56d27c6757f0..4f5a8f37ab62e 100644
--- a/src/test/test_pivx.cpp
+++ b/src/test/test_pivx.cpp
@@ -17,6 +17,7 @@
 #include "net_processing.h"
 #include "rpc/server.h"
 #include "rpc/register.h"
+#include "sapling/sodium_sanity.h"
 #include "script/sigcache.h"
 #include "sporkdb.h"
 #include "txmempool.h"
@@ -43,6 +44,7 @@ std::ostream& operator<<(std::ostream& os, const uint256& num)
 BasicTestingSetup::BasicTestingSetup(const std::string& chainName)
     : m_path_root(fs::temp_directory_path() / "test_pivx" / strprintf("%lu_%i", (unsigned long)GetTime(), (int)(InsecureRandRange(1 << 30))))
 {
+    assert(init_and_check_sodium() != -1);
     ECC_Start();
     SetupEnvironment();
     InitSignatureCache();