Falaj 17: Banner Grab

A network service usually announces itself when you connect: a greeting line, a name, sometimes a version. That greeting is a banner, and reading banners is one of the simplest ways to find out what is running where. It is also why security teams remove version details from banners they do not need to publish.

One machine on the network, named in the services file in your home directory, runs four small services on different ports. The ports helper lists which ports are open, and nc connects to a port and shows what it says. One service is the tally desk, and its banner carries the password for the next level. Connect to each in turn and read what it announces.

You are only connecting to your own lab network here, and the machine is a simulation. This is a simulated shell over invented files: it understands a teaching subset of commands, and help lists them. When you have the password for level 18, run login 18 <password> or paste it into the answer box.