This is not original work, I found it here on Github.  Interesting idea with a somewhat limited use... in my opinion.  The description states:  "c# reverse shell poc that also does TLS".  I keep reading that CSharp is the new PowerShell but as far as I can tell, CSharp payloads are getting detected so maybe that ship has passed.  I will say that this shell goes undetected but it does require the arguments so it's not something you can get a user to click on. 

One final thought -- you only need Program.cs which can be compiled in the .NET folder.

We call csc.exe to compile our shell:


We then execute our file giving it the IP and port of our attacking host:

With our handler setup:

We catch our inbound connection.