In many regards, 2020 has felt like a collective Blue Screen of Death. However, a raging virus was not enough to keep DEF CON from happening. This year it booted into Safemode, an online-only version of the popular security conference. Along with it, the titular DEF CON CTF reimagined itself for a virtual future.

PlaidCTF 2020, with the theme Ready Pwner One, ran from April 17 to 19. We had a lot of very difficult problems, and all of them got solved… except for one:

At this point, it should probably come as little surprise that Catalog is one of mine; I don’t have the best record at having all of my problems solved (see: Toaster Wars Stormy Flag, idIoT: Lights). Here, I’ll discuss the intended solution to the problem, and a little behind-the-scenes look at what led me to write this problem and what I’d do differently if I had the chance to do it again.

For PlaidCTF this year, I created a demake of The Witness in Hypercard. Since most of the technology I used is over 20 years old, and a lot of the documentation seems lost to time, I created a short video that discusses how I made it, and what resources I used in order to make it happen.

About 6 months ago, I had some downtime while transitioning jobs and decided to look for a project to entertain myself with. I had previously run into Minamaxir’s GPT-2 Magic Card Generator and thought it could be quick and fun to apply that idea to a hobby of my own, Dungeons and Dragons. Such a generator could end up being a useful tool, but more likely I figured I would end up with a toy project to play with while quickly teaching myself a little more about GPT-2. Unfortunately, it didn’t end up being quite as simple as I had imagined.

It occurred to me about a month ago that I never published author writeups for the “Toaster Wars: Going Rogue” CTF problems from PicoCTF 2017 and PlaidCTF 2017, which is particularly troubling since one of them wasn’t actually solved in contest! To remedy this, and in celebration of the release of a new game in the series that inspired these problems later this week, I’ll be posting writeups for all of the Toaster Wars problems over the course of the week.

For day four, I’ll be talking about the Blazing Flag from PlaidCTF 2017.