diff --git a/oauth-auth-code/csharp/authorization_code_aspdotnet.csproj b/oauth-auth-code/csharp/authorization_code_aspdotnet.csproj
index 964c96a..b7fe2c1 100644
--- a/oauth-auth-code/csharp/authorization_code_aspdotnet.csproj
+++ b/oauth-auth-code/csharp/authorization_code_aspdotnet.csproj
@@ -5,7 +5,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
+    <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
   </ItemGroup>
 
 </Project>