A legitimate website that tunnels client/server communications for covert command execution.
TrevorC2 is a client/server model for masking command and control through a normally browsable website. Detection becomes much harder as time intervals are different and does not use POST requests for data exfil.
There are two components to TrevorC2 - the client and the server. The client can be configured to be used with anything. In this example it's coded in Python but can easily be ported to C#, PowerShell, or whatever you want. Currently the trevorc2_client.py supports Windows, MacOS, and Linux. You can always byte compile the Windows one to get an executable, but preference would be to use Windows without having to drop an executable as a stager.
The way that the server works is by tucking away a parameter thats right before the parameter. This is completely configurable, and it's recommended you configure everything to be unique in order to evade detection.
TrevorC2 supports the ability to handle multiple shells coming from different hostnames. The way TrevorC2 works is it will identify new hostnames as sessions. You can interact with the sessions once you execute a command. If you have multiple sessions, you can type a command and interact with that session based on the session number stored globally.
When first starting TrevorC2, you can type help or ? for additional information. Basic command usage is "list" which will list any active shells or none at all, or "interact " to interact with the shell you want.
You can always type back/exit within a shell, it will still remain active and not actually kill the shell.