diff --git a/Tests/CSharpCore/Tests.NetStandard.csproj b/Tests/CSharpCore/Tests.NetStandard.csproj
index 4dc61a9d..874eefb7 100644
--- a/Tests/CSharpCore/Tests.NetStandard.csproj
+++ b/Tests/CSharpCore/Tests.NetStandard.csproj
@@ -18,6 +18,7 @@
     <TargetFrameworks Condition="'$(IsNet90Supported)' == 'true' ">$(TargetFrameworks);net9.0</TargetFrameworks>
     <TargetFrameworks Condition="'$(OS)' == 'Windows_NT'">$(TargetFrameworks);net471</TargetFrameworks>
     <TestTfmsInParallel>false</TestTfmsInParallel>
+    <EnableUnsafeBinaryFormatterSerialization>true</EnableUnsafeBinaryFormatterSerialization>
   </PropertyGroup>
   <ItemGroup>
     <EmbeddedResource Include="**\*.resx" />
@@ -44,9 +45,7 @@
   </ItemGroup>
   <ItemGroup Condition="'$(TargetFramework)'!='net471'">
     <PackageReference Include="System.Net.Sockets" Version="4.3.0" />
-  </ItemGroup>
-  <ItemGroup Condition="'$(TargetFramework)'=='net8.0'">
-    <PackageReference Include="System.Runtime.Serialization.Formatters" Version="8.0.0-*" />
+    <PackageReference Include="System.Runtime.Serialization.Formatters" Version="9.0.0-*" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\SharpSnmpLib\SharpSnmpLib.csproj" />