s4r's bitflip



1:53 PM 02/08/2019


Unix/linux etc.


A crackme designed to run on Linux x86-32. It has been generated from a custom script. It'll prompt the user for a string and will start to validate the password when the 0x40 bytes buffer is filled. The objective is to print the "Well done" message by submitting the good password. Patching is not allowed, I don't even know if it's possible. I set the difficulty to 5, but it's without doubt the hardest crackme I've made. It took me a lot of time to build so I hope you'll like it. SHA256: c10dd3294e2e5c93ba420fd7b651cceb4695bc9fbac4031ac662bae1db0ff031 bitflip

pinnn on 5:39 PM 03/02/2019: Hi s4r! Is it normal that program crashed on ubuntu 14 when i pass 0x40 input with error: Bus error (core dumped)

pinnn on 4:01 PM 03/05/2019: Patch is possible). 0x804913e = 0x4bbc40 and you get "well done". Very good crackme, solution will be soon)

4aca7f6c on 11:54 AM 05/11/2019: Finally got around to doing this one. Ingenious crackme! Intimidating at first, but not too bad if you think about it in the right way. Thank you!