s4f3 With Phil242, we concentrated on this interesting hardware challenge of Karim. Description A binary challenge.elf is provided. Reconnaissance with AI 1 2 $ file challenge.elf challenge.elf: ELF 32-bit LSB executable, Tensilica Xtensa, version 1 (SYSV), statically linked, with debug_info, not stripped I try to get some initial thoughts with r2mcp. It doesn’t help me very much, but gives me some idea about the context: The flag is formatted BA25{.....} and it is redacted in the binary The binary was developed using Arduino My initial prompt:

Hack.lu CTF 2025 I played this CTF in a different way: very relaxed, only looked at 4 challenges I was interested in, solved 3 ;P and nearly 4… Did not even peek at the other challenges (see Conclusion about that). All challenges at Hack.Lu were organized as if they were items in an IKEA shop, including their names: MANUAL: I flagged this crypto challenge entirely with ChatGPT. I didn’t even need to understand it.

BruCON 2025 ICS Hacking Village The ICS Hacking Village at BruCON 2025 was offering a cool challenge, where water flow in Hacktopia city was malfunctioning because of a cyber attack. The goal of the challenge was to stop the overflow in a water tower and re-open water from a secondary water tank for water to flow again in the building. Each participant was supplied with a control box consisting of a M5 Core connecting to a few sensors, buttons, potentiometers, and connected to a water tank.