@blackb6a played TSJ CTF and CODEGATE CTF this weekend. Both of the CTFs had a bunch of epic (and hard-ish) crypto challenges, which made our head scratched for days.
We were two points behind @balsnctf few minutes before the game ends and I found one more flag. It is proud to tell that we won TSJ CTF 🎉!
Anyway, I will compile writeups for (at least) three challenges for TSJ CTF, namely Cipher Switching Service, Signature and Genie. I will go through Cipher Switching Service as the first part of the series.
DiceCTF is an annual CTF competition prepared by @dicegangctf. The challenges are great and we had a lot of fun solving them. I might be compiling writeup for a number of them, which depends if I had time.
I will first cover on a crypto challenge called commitment-issues, which had 16 solves (out of 1127 participating teams). @grhkm2023 and I spent a good 3 to 4 hours working on this challenge.