diff --git a/eng/Packages.props b/eng/Packages.props
index 489ea061c95..ac8df77f629 100644
--- a/eng/Packages.props
+++ b/eng/Packages.props
@@ -25,7 +25,6 @@
     <PackageVersion Include="System.Reflection.MetadataLoadContext" Version="$(SystemReflectionMetadataLoadContextVersion)" />
     <PackageVersion Include="System.Resources.Extensions" Version="$(SystemResourcesExtensionsPackageVersion)" />
     <PackageVersion Include="System.Runtime.CompilerServices.Unsafe" Version="$(SystemRuntimeCompilerServicesUnsafeVersion)" />
-    <PackageVersion Include="System.Security.Permissions" Version="$(SystemSecurityPermissionsVersion)" />
     <PackageVersion Include="System.Security.Principal.Windows" Version="$(SystemSecurityPrincipalWindowsVersion)" />
     <PackageVersion Include="System.Text.Encoding.CodePages" Version="$(SystemTextEncodingCodePagesVersion)" />
     <PackageVersion Include="System.Text.Json" Version="$(SystemTextJsonVersion)" />
diff --git a/eng/Version.Details.xml b/eng/Version.Details.xml
index 2758bb113ec..4683ffbca57 100644
--- a/eng/Version.Details.xml
+++ b/eng/Version.Details.xml
@@ -52,11 +52,6 @@
       <Uri>https://github.com/dotnet/runtime</Uri>
       <Sha>d099f075e45d2aa6007a22b71b45a08758559f80</Sha>
     </Dependency>
-    <!-- Necessary for source-build. This allows the live version of the package to be used by source-build. -->
-    <Dependency Name="System.Security.Permissions" Version="7.0.0">
-      <Uri>https://github.com/dotnet/runtime</Uri>
-      <Sha>d099f075e45d2aa6007a22b71b45a08758559f80</Sha>
-    </Dependency>
     <Dependency Name="System.Text.Json" Version="7.0.3">
       <Uri>https://github.com/dotnet/runtime</Uri>
       <Sha>5b20af47d99620150c53eaf5db8636fdf730b126</Sha>
diff --git a/eng/Versions.props b/eng/Versions.props
index 58866d8cc69..5c8665f07fb 100644
--- a/eng/Versions.props
+++ b/eng/Versions.props
@@ -38,7 +38,6 @@
     <SystemReflectionMetadataLoadContextVersion>7.0.0</SystemReflectionMetadataLoadContextVersion>
     <SystemReflectionMetadataVersion>7.0.0</SystemReflectionMetadataVersion>
     <SystemResourcesExtensionsPackageVersion>7.0.0</SystemResourcesExtensionsPackageVersion>
-    <SystemSecurityPermissionsVersion>7.0.0</SystemSecurityPermissionsVersion>
     <SystemSecurityPrincipalWindowsVersion>5.0.0</SystemSecurityPrincipalWindowsVersion>
     <SystemTextEncodingCodePagesVersion>7.0.0</SystemTextEncodingCodePagesVersion>
   </PropertyGroup>
diff --git a/src/Framework/Microsoft.Build.Framework.csproj b/src/Framework/Microsoft.Build.Framework.csproj
index 724e1a38496..c0da0474e6c 100644
--- a/src/Framework/Microsoft.Build.Framework.csproj
+++ b/src/Framework/Microsoft.Build.Framework.csproj
@@ -15,10 +15,6 @@
     <PackageReference Include="Microsoft.CodeAnalysis.Collections" PrivateAssets="all" />
   </ItemGroup>
 
-  <ItemGroup Condition="'$(TargetFrameworkIdentifier)' != '.NETFramework'">
-    <PackageReference Include="System.Security.Permissions" />
-  </ItemGroup>
-
   <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework'">
     <!-- Promote CompilerServices.Unsafe from the old version we get from System.Memory on net472. -->
     <PackageReference Include="System.Runtime.CompilerServices.Unsafe" />
diff --git a/src/Shared/ExceptionHandling.cs b/src/Shared/ExceptionHandling.cs
index a7ef74e8737..eca284ecb64 100644
--- a/src/Shared/ExceptionHandling.cs
+++ b/src/Shared/ExceptionHandling.cs
@@ -167,7 +167,9 @@ internal static bool IsIoRelatedException(Exception e)
         internal static bool IsXmlException(Exception e)
         {
             return e is XmlException
-                || e is XmlSyntaxException
+#if FEATURE_SECURITY_PERMISSIONS
+                || e is System.Security.XmlSyntaxException
+#endif
                 || e is XmlSchemaException
                 || e is UriFormatException; // XmlTextReader for example uses this under the covers
         }
diff --git a/src/Tasks/Microsoft.Build.Tasks.csproj b/src/Tasks/Microsoft.Build.Tasks.csproj
index 72ea1091d20..e11a7698f31 100644
--- a/src/Tasks/Microsoft.Build.Tasks.csproj
+++ b/src/Tasks/Microsoft.Build.Tasks.csproj
@@ -1008,7 +1008,6 @@
     <PackageReference Include="System.CodeDom" />
     <PackageReference Include="System.Security.Cryptography.Pkcs" />
     <PackageReference Include="System.Security.Cryptography.Xml" />
-    <PackageReference Include="System.Security.Permissions" />
 
     <Content Include="$(NuGetPackageRoot)microsoft.net.compilers.toolset\$(MicrosoftNetCompilersToolsetVersion)\tasks\netcore\**\*" CopyToOutputDirectory="PreserveNewest" LinkBase="Roslyn" />
   </ItemGroup>
diff --git a/src/Utilities/Microsoft.Build.Utilities.csproj b/src/Utilities/Microsoft.Build.Utilities.csproj
index b9296ffc4e4..5b9a22eba36 100644
--- a/src/Utilities/Microsoft.Build.Utilities.csproj
+++ b/src/Utilities/Microsoft.Build.Utilities.csproj
@@ -32,7 +32,6 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFrameworkIdentifier)' == '.NETStandard'">
-    <PackageReference Include="System.Security.Permissions" />
     <PackageReference Include="System.Text.Encoding.CodePages" />
   </ItemGroup>