Netcat with encryption for Linux and Windows – This is the classic network utility Netcat, with Twofish encryption. Includes Windows and Linux source and binary. To make it secure you need to change the hardcoded key.
You can download it from the following link: https://packetstormsecurity.com/files/download/23167/nc_twofish.tgz
Source: https://packetstormsecurity.com/files/23167/nc_twofish.tgz.html