Signatus is a vulnerable C++ server to practice Win 32 exploitation on, as well as reverse engineering.
To try and solve this challenge, you should not look at the source code of the server. Dowload the exe in the releases section (Signatus.exe), and create an exploit which will spawn a reverse shell by reverse engineering.
A possible solution is included in the Exploit/ folder. If you want to solve the challenge yourself don't look at it beforehand obviously.