How can NetCat be used to forward SSH traffic in a pivot scenario?

• A. NetCat can only listen for connections and cannot forward traffic.
• B. NetCat can only forward traffic if TLS is used.
• C. NetCat can relay SSH traffic by binding to a local port and connecting to the remote SSH server.
• D. NetCat automatically tunnels SSH without any configuration.

Answer: (D)

NetCat can act as a simple TCP relay, which is what lets you forward SSH traffic through a pivot. The idea is to set up NetCat on the pivot to listen on a local port and, for each incoming connection, have NetCat connect onward to the internal SSH server. This creates a bridge that carries SSH traffic from the attacker through the pivot to the target.

A common way to do this is to bind a port on the pivot and pipe the traffic to the internal SSH host and port. For example, you can have the pivot listen on a chosen port (like 2222) and forward everything that arrives there to the internal SSH server on port 22, using a command such as nc -l 2222 | nc internalhost 22. With this in place, you can connect an SSH client to the pivot on port 2222, and the data is transparently relayed to the internal SSH service, with the responses flowing back through the same path.

This technique relies on configuring NetCat to establish the two connections (client to pivot and pivot to internal SSH) and to pipe the data between them. It’s a practical, if manual, tunneling method for pivot scenarios. It’s not automatic in the sense of needing no configuration; you must set up the listening port on the pivot and direct the forward connection to the remote SSH server.