diff --git a/eng/Versions.props b/eng/Versions.props
index 79fae3e14045..f997d3d5cef6 100644
--- a/eng/Versions.props
+++ b/eng/Versions.props
@@ -199,6 +199,7 @@
     <MicrosoftVSSDKBuildToolsVersion>15.9.3032</MicrosoftVSSDKBuildToolsVersion>
     <AnalyzersSystemTextJsonVersion>$(SystemTextJsonVersion)</AnalyzersSystemTextJsonVersion>
     <!-- Stable dotnet/corefx packages no longer updated for .NET Core 3 -->
+    <RepoTasksSystemSecurityCryptographyXmlVersion>8.0.3</RepoTasksSystemSecurityCryptographyXmlVersion>
     <MicrosoftCSharpVersion>4.7.0</MicrosoftCSharpVersion>
     <MicrosoftWin32RegistryVersion>5.0.0</MicrosoftWin32RegistryVersion>
     <NETStandardLibraryVersion>2.0.3</NETStandardLibraryVersion>
diff --git a/eng/tools/RepoTasks/RepoTasks.csproj b/eng/tools/RepoTasks/RepoTasks.csproj
index d1fa1d66d7a6..36dacb13de4f 100644
--- a/eng/tools/RepoTasks/RepoTasks.csproj
+++ b/eng/tools/RepoTasks/RepoTasks.csproj
@@ -29,6 +29,8 @@
     <PackageReference Include="Microsoft.Build.Framework" Version="$(MicrosoftBuildFrameworkVersion)" />
     <PackageReference Include="Microsoft.Build.Tasks.Core" Version="$(MicrosoftBuildTasksCoreVersion)" />
     <PackageReference Include="Microsoft.Build.Utilities.Core" Version="$(MicrosoftBuildUtilitiesCoreVersion)" />
+    <!-- Manually updated version from 6.0.0 to address CVE-2023-29331 -->
+    <PackageReference Include="System.Security.Cryptography.Xml" Version="$(RepoTasksSystemSecurityCryptographyXmlVersion)" />
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == 'net472'">