You may have seen a few more geek notes on here of late. I’ve really enjoyed jumping into CTFs. My objective isn’t to win, but to find more ways to solve puzzles.

This weekend’s adventures were a little different, though. My company sponsors UMBC’s CyberDawgs team, and they’ve asked us to contribute challenges to their upcoming CTF. I tasked our IRAD team with coming up with a few and I wrote a couple, as well. So this weekend I spent some normalizing our submissions’ README files and doing a final test of the submissions.

One of the submissions was really giving me trouble. The IRAD team member who’d developed it had demonstrated it to us, but the solution instructions in the README just weren’t “clicking” to then be able to reproduce a solve, much less help anyone else understand how to solve. It’s customary in CTFs to have a Discord channel where mentors can offer assistance to those on the right track; given that I don’t want to be up all night myself providing that support, thought it best to provide a walkthrough for someone else..

Not only did I “crack” it (helped, of course, by the solution instructions in his README), but then I was able to provide a linked reproducible recipe using a tool called CyberChef that is really useful for a lot of CTF grunt work. I’m avoiding linking to the recipe or giving any more info on the challenge, of course, given that there’ll be hopefully lots of folks taking a crack at it in early May. I’m now more confident, though, that there may be some folks who solve it AND I better understand a particular kind of encryption approach.