StageStrike
A custom Cobalt Strike stager written in C.. is how the project started.
There's a high possiblity that I haven't looked hard enough, but I have not found an open source stager that works with CS. So my goal is to make a stager that is simple, and load stages hosted by CS in memory. This project was inspired by Mudges own Metasploit payload stager here: https://github.com/rsmudge/metasploit-loader And explained here https://blog.cobaltstrike.com/2013/06/28/staged-payloads-what-pen-testers-should-know/
I'm guessing most mature teams have their own stager whipped up already, but for ones looking for inspiration, here is one implementation using WindowsApi.
I would like to in the future use other methods of executing the stage in memory as outlined by this great blog post: https://www.contextis.com/en/blog/a-beginners-guide-to-windows-shellcode-execution-techniques
-Dynamic Allocation of Memory
-Function Pointer Execution
-.TEXT-Segment Execution
-RWX-Hunter Execution
But for now it'll just be Dynamic Allocation of memory using Win32.