OAuth Authentication with TLS 1.2 in WPF Window Application .NET Framework 4.0

Question

I have a WPF window application on .NET Framework 4.0 using OAuth authentication.

I used Microsoft.Identity.Client library to implement OAuth authentication.

When we see logs in Azure monitor all users sign in with Legacy TLS (TLS 1.0,1.1,3 DES). We want to sign in with TLS 1.2.

How can we achieve this?

We have successfully enabled TLS 1.2 for MVC web application user sign in with TLS 1.2 which runs on .NET Framework 4.5.

Answer 1

Anything .NET Framework 4.0 or below does not support TLS 1.2 and .NET 4 only supports up to TLS 1.0. In .NET Framework 4.0 the SecurityProtocolType doesnot have any entry for TLS1.2, So you must either update the runtime version or switch to TLS 1.0. We see that you have successfully enabled TLS 1.2 for MVC web application user sign in which runs on .NET Framework 4.5, because TLS 1.2 is supported by .NET4.5, however its not a default protocol. To use it, you must opt-in.