This is a php shell that offers various connect-back methods, the ability to read files, grab source, execute code, etc.
You can download it from the following link: https://packetstormsecurity.com/files/download/108693/priv8-2012-bypass-shell.txt
Source: https://packetstormsecurity.com/files/108693/Priv8-2012-Bypass-Shell.html