b3n on 2019-05-17 18:13:
First off, this is not a "Level 1" crackme by any stretch of the imagination. I'm a beginner and thought it was strange this was placed as a Level 1. The Anti-Debug alone makes it qualified to be at least a Level 2. On top of that, the binary is stripped!! So this is Level 2 or Level 3 in my opinion.
With that being said, I was able to learn a lot doing this challenge. I spent the last couple of weeks working on it in my free time. Probably 5 or 6 hours total, maybe more. I wasn't familiar with GDB, so I had to learn that pretty well. I didn't have the slightest clue how to get around anti-debug, so I had to learn that trick. I didn't know how to find main in a stripped binary, so I had to learn how to do that. I'm a programmer so I was able to follow the all of the inline function calls and memory manipulation pretty well, but it was still tough following all of the functions.
All in all, it was a really fun challenge and I learned a lot. I got the flag and I'm happy to finally be "Mr. Satan". But I was seriously pissed while solving this because I was looking for an easy "Level 1" challenge that a newbie like myself could solve in 30 minutes, but instead I got this crazy shit 'Much0l0k0' that the author 'paypain' put at "Level 1". I cursed his name many times solving this. But I appreciate it because in the end, I learned a lot.
If there is any interest I can put up the guide to how I solved it. Just leave a comment and let me know.
paypain on 2019-05-18 01:35:
+b3n Thank you very much for your comment, i appreciate it! my next crackme will have a easter egg in your name.
groot4 on 2019-05-19 02:55:
Good one i have solved it!!!
nshmadhani on 2019-06-12 06:16:
What is the Password Supposed to be
ker2x on 2019-06-24 17:39:
Certainly not a level 1 for sure, i almost cracked it but i have a question : did you play with the entry point ? or is it ghidra that messed up stuff ?
ker2x on 2019-06-24 18:51:
forget my previous comment. brain fart.
paypain on 2019-06-26 15:12:
+ker2x nice solution bro! u figure out the malloc tip. PS: Is 'Mr.' hahahaha
BinaryNewbie on 2019-07-30 07:40:
Nice crackme, at least lv 2, but definitely not lv 3.
I will submit my write up soon.
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Solution by juju2964 on 2019-05-10 20:53: All info provided in the text file - took not too long and learnt about switch statements :D
Solution by ker2x on 2019-06-24 20:02: Solving it was both fun and painful because it's not a LVL1.
Fun because i solved it, painful because i almost gave up.
I describe the solution step by step so if you struggle you can read the first few steps that give you a good head start. I don't give the actual solution until the end.