Pivoting

Meterpreter is a Metasploit attack payload that offers an interactive shell from which an attacker can execute code to the target machine. It has an autoroute exploit that can route the network in such a way that internal IP is accessible from ouside by adding route toward an internal network.

In the following video, an attacker use the autoroute exploit from Meterpreter to get an access to an internal vulnerable machine in a target network.