diff --git a/SlimStateMachine/SlimStateMachine.csproj b/SlimStateMachine/SlimStateMachine.csproj
index dd584d2..842c7fc 100644
--- a/SlimStateMachine/SlimStateMachine.csproj
+++ b/SlimStateMachine/SlimStateMachine.csproj
@@ -30,7 +30,7 @@
 	</ItemGroup>
 
 	<ItemGroup>
-	  <PackageReference Include="System.Collections.Immutable" Version="9.0.4" />
+	  <PackageReference Include="System.Collections.Immutable" Version="9.0.11" />
 	</ItemGroup>
 
 </Project>
\ No newline at end of file