diff --git a/src/SourceBuild/content/eng/Versions.props b/src/SourceBuild/content/eng/Versions.props
index 74c73d7fb..618e11fcd 100644
--- a/src/SourceBuild/content/eng/Versions.props
+++ b/src/SourceBuild/content/eng/Versions.props
@@ -25,7 +25,7 @@
     <PrivateSourceBuiltSdkVersion>9.0.100-preview.4.24179.1</PrivateSourceBuiltSdkVersion>
     <PrivateSourceBuiltArtifactsVersion>9.0.100-preview.4.24179.1</PrivateSourceBuiltArtifactsVersion>
     <!-- msbuild -->
-    <MicrosoftBuildVersion>15.7.179</MicrosoftBuildVersion>
+    <MicrosoftBuildVersion>17.8.3</MicrosoftBuildVersion>
     <!-- runtime -->
     <MicrosoftExtensionsFileSystemGlobbingVersion>9.0.0-preview.2.24128.5</MicrosoftExtensionsFileSystemGlobbingVersion>
     <MicrosoftExtensionsLoggingConsoleVersion>9.0.0-preview.2.24128.5</MicrosoftExtensionsLoggingConsoleVersion>
diff --git a/src/SourceBuild/content/eng/tools/init-build.proj b/src/SourceBuild/content/eng/tools/init-build.proj
index 6c76a0b14..5c19bbad5 100644
--- a/src/SourceBuild/content/eng/tools/init-build.proj
+++ b/src/SourceBuild/content/eng/tools/init-build.proj
@@ -94,12 +94,12 @@
     </Touch>
   </Target>
 
-  <!-- Build msbuild tasks for the poisoning feature. -->
+  <!-- Build msbuild tasks for the poisoning feature even when EnablePoison!=true to validate that the task project
+       builds as EnablePoison=true isn't exercised in PR validation. -->
   <Target Name="BuildLeakDetection"
           DependsOnTargets="ExtractToolPackage;BuildMSBuildSdkResolver"
           Inputs="$(MSBuildProjectFullPath)"
-          Outputs="$(BaseIntermediateOutputPath)BuildLeakDetection.complete"
-          Condition="'$(EnablePoison)' == 'true'">
+          Outputs="$(BaseIntermediateOutputPath)BuildLeakDetection.complete">
     <MSBuild Projects="tasks\Microsoft.DotNet.SourceBuild.Tasks.LeakDetection\Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj"
              Targets="Restore"
              Properties="MSBuildRestoreSessionId=$([System.Guid]::NewGuid())" />
diff --git a/src/SourceBuild/content/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj b/src/SourceBuild/content/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj
index 3622b24e4..e37a947e1 100644
--- a/src/SourceBuild/content/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj
+++ b/src/SourceBuild/content/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection/Microsoft.DotNet.SourceBuild.Tasks.LeakDetection.csproj
@@ -6,7 +6,6 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.Build" Version="$(MicrosoftBuildVersion)" />
     <PackageReference Include="Microsoft.Build.Utilities.Core" Version="$(MicrosoftBuildVersion)" />
   </ItemGroup>