I've recently had another need to fix an issue in frida and I had to re-discover some things about how to develop for this tool. With that in mind, this blog post is meant to cover some quick tips for how to go about developing or fixing frida's code base. Mostly so I can reference it later once I forget how it works again...

This challenge was actually a re-release of the original challenge "Patch Tuesday", which the author accidentally left the flag in the original binary. This version is more interesting and is an example of using revenge to apply a Windows patch.

This specific challenge was not actually solved by me during quals. Aegis officially scored and I'm sure others helped out. That said, I like to look at challenges afterwards and identify what I could do to solve it more efficiently next time. What follows is a walk-through on solving this challenge with my revenge tool.

Using this CSAW qualifier as a means to test our the tool called revenge I've been working on. This challenge was an easy reversing one, but it was made easier through revenge.


beleaf: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/l, for GNU/Linux 3.2.0, BuildID[sha1]=6d305eed7c9bebbaa60b67403a6c6f2b36de3ca4, stripped

Description: I forgot admin’s product key…

First off, this challenge was listed as 200pts. I was the 7th to solve it with about 45 minutes left in the contest. Other 200 point challenges had many more solves (for instance Baby ROP was 200pt and had 80+ solves). Unfortunately, I got sucked into this and needed to finish it for my own sanity. That said, it was good challenge, just not realistically 200 points.