This is a lab I created during my eCPPT exam preparation to practice pivoting techniques with chisel, "a fast TCP/UDP tunnel, transported over HTTP, secured via SSH". While it's true that most of that exam can be completed with Metasploit only, it's always helpful to have a number of tools in your pocket.
The lab uses Docker to create three instances of the tleemcjr/metasploitable2 image. Modeled after TryHackMe's Wreath machine, the idea is to reach the third Metasploitable image, as shown in the topoglogy below, which was made with PlantUML.
The recommended setup is to host the lab on a VM running Docker (pwn-me in
the topology) which is on the same subnet as the attacker machine. This way,
the attacker machine can't use its own Docker routing to reach the target. For
example, in VirtualBox, one could put the attacker and target VMs on the NAT
network. The SEED Labs Ubuntu 20.04
VM comes with Docker
pre-installed, which makes it an excellent choice for the target machine. If
memory is a concern, you could run it headless.
Mostly I followed 0xdf's chisel cheat sheet, ensuring I could repeat all the things he demonstrates there.
Thanks to the practice I did in this lab, I went into my eCPPTv2 exam with the confidence that I would have no trouble moving around the network.