Advent of Code is a coding competition, with one new challenge per day during December. I started writing the core of my own solutions, then I realized this wouldn’t be very interesting because (1) my own code is often very naive compared to the best ones, (2) the article was starting to get very long. Instead, I will focus only on things I learned or already knew but experienced doing the challenges.

BruCON 2023 CTF Many challenges, many flags in this CTF. Our team happily ranked 6th / 64. Positive aspects: It is really interesting to have a full document with network and architecture diagrams of what looks like a real beer brewery. It makes the challenges feel real and I appreciated the time the organizers took to prepare such a scenario I enjoyed the PLC challenges where we used and hacked into real PLCs.

This is a write-up for some of the PLC / Critical Infrastructure challenges of BruCON. PLC: The Secret Ingredient This is an OT challenge where we interact with a real PLC. We are asked to “get the PLC program and rescue the company secret located in datablock 23”. The IP address of the PLC is 35.232.66.239:102. I solved this one with a team mate, and he did the most difficult part.