Sometimes, especially in the time of COVID-19, you can’t go onsite for a penetration test. Or maybe you can only get in briefly on a physical test, and want to leave behind a dropbox (literally, a box that can be “dropped” in place and let the tester leave, no relation to the file-sharing company by the same name) that you can remotely connect to. Of course, it could also be part of the desired test itself if incident response testing is in-scope – can they find your malicious device?
In all of these cases, one great option is a small single-board computer, the best known of which is the Raspberry Pi. It’s inexpensive, compact, easy to come by, and very flexible. It may not be perfect in every case, but it gets the job done in a lot of cases.
I’ll use this opportunity to discuss the setups I’ve done in the past and the things I would change when doing it again or alternatives I considered. I hope some will find this useful. Some familiarity with the Linux command line is assumed.