Reverse-Engineering Challenge Write-ups

This repository contains write-ups and solutions for various challenges from the crackmes.one website. Each folder corresponds to a specific challenge and is organized by the challenge name and its author.

Repository Structure

• Folder Name: Each folder is named after the challenge and the author, e.g., challenge_name_author or challenge_name depending on if the name is unique enough.
  • solution.txt: This file contains a high-level overview of the steps taken to solve the challenge, explaining the thought process and techniques used.
  • keygen.py (if applicable): A keygen script that generates valid user/password combinations for the challenge, where feasible.
  • decompilation.c/.cpp (if applicable): Sometimes I write decompilations for the challenges. Don't treat them as source code, they are not since I just replicate the high-level operations.

How to Use

To explore a solution, navigate to the corresponding folder, read the solution.txt file for guidance, and run keygen.py if you’d like to generate keys for testing. Decompilations, inside the decompilation.c/.cpp file, can be compiled with the compiler of your choice and run without much thought. I develop them on linux, so windows users might face issues(I try to keep them as cross-platform as I can).

Plans

• Currently on vacation, I will come back on the second week of January. Till then I'll be studying reverse engineering, prepare for greatness. Disregard the next point :).

• I will try to solve at least one difficult crackme a week and multiple easier ones, adding the write-ups to this repository. I am currently in Uni so I don't have infinite time but can usually spend an hour a day on it.

• I have started developing a GUI app called Harpocrates, which can be found on my github profile. I will try to keep it updated and add features semi-regularly. More information can be found there.

Contributions

Feel free to suggest improvements to existing solutions or request solutions to challenges. I usually compose the write-ups while I'm tired so if there are any mistakes in the phrasing or if you want something to be explained in more detail, let me know.

Notes

I am still a student of this craft and thus many of my solutions may be sub-optimal or may use bad habits. Make sure to study other peoples solutions too.