Undetectable Backdoor Utilities and Metasploit Module

Cryptcat Project:
This is an advanced utility based on netcat and one that uses an
encryption technique with the ports of Windows, BSD and Linux.
MOCAT backdoor:
This one is based on the cryptcat project and works on client and
server phenomena, meaning it has two executables: one for windows and
the other for Linux. All  communications of MOCAT are encrypted.
Ncat :
Ncat is a wonderful