CTF Write-Ups

Write-ups on challenges for various CTFs (cyber security competitions).

I'll try to explain how to do each challenge to the best of my ability, as well as provide example and proof-of-concept code.

Thanks to pcw109550 for the inspiration, the format here may look similar :)

2023

• DEFCON CTF Qualifiers - May 26-28
  • OMGzip - Understand a custom compression algorithm written in Python, and write a decryption algorithm
• DiceCTF - February 3-5
  • Provaby Secure 2 - Prove a custom cryptosystem insecure under IND_CCA2