SSTIC challenge 2020 writeup

Guillaume Quéré

This is my writeup for the 2020 SSTIC’s challenge.

The SSTIC is the biggest french security conference. Its annual challenge is generally considered to be a difficult reversing challenge that involves fun technologies.

Looking back on the past few weeks, I think it took me more than 120 hours to solve the whole challenge, which is gargantuous. Nevertheless, it’s the first year I managed to finish it so I’m really happy. Note that I’m a novice reverser whereas this year’s winner has flagged all steps in 36 hours total, gratz to you @0xf4b.

I’m not spoiling you the technologies involved yet, they’re quite fun and it’s a part of the challenge to discover them on the go. If you’re a hardcode reverser, jump to step 4.

Here are the 6 steps: