SubShell is a python command shell used to control and execute commands through HTTP requests to a webshell. SubShell acts as the interface to the remote webshells.
Weevely is a command line web shell dynamically extended over the network at runtime, designed for remote server administration and penetration testing.
https://github.com/jubal-R/TinyWebShell
A simple php web shell and client with an interactive console for use in CTFs, wargames, etc. The goal is to keep the web shell tiny by moving as much code as possible to the client side.
https://github.com/0verl0ad/HideShell
A tool to ofuscate big webshells (c99, r57...). Can hide your webshell from AV, LMD, Neopi, Web Shell Detector, etc.