D4RKFL0W's crackme2-be-D4RK_FL0W



10:40 PM 03/22/2019


Unix/linux etc.


A second simple crackme(Aimed at beginners). Any feedback welcome.

darkcrow on 3:54 PM 03/27/2019: An awesome crackme and a easy one. The key was a bit harder to find, but when its location is discovered, the crackme is cracked. Congratulations for your crackme :)

MrCobalt on 4:33 PM 03/28/2019: This one was fun and challenging for me and I learned a lot too! Thanks for making it, and I hope you make more!

Buh13246 on 3:35 AM 04/04/2019: i'm not able to crack it :( ... But i think you have an invalid memory read in function check_password 'if (pass_in[(long)i] != pass[(long)i])'. pass is a array of 16 chars, so pass[0] and pass[15] are legal. if (0xf

Buh13246 on 3:37 AM 04/04/2019: if (0xf

Buh13246 on 3:40 AM 04/04/2019: (i hope it wont be cutted this time...) if (0xf < i) { //16 is not less than 16 return 1; } // so pass[16] will be accessed but is invalid

Buh13246 on 3:46 AM 04/04/2019: I'm so dump..... sry for everything 0xf == 15 ... it's just to late... its 5:46AM on my country.

pukar_giri on 6:42 PM 04/16/2019: D4RKFL0W i really wonder how did you code that xxx function of yours i see it uses the repnz scasb technique to find the length of the string but i don't find any c++ equivalent that could compile down to it can you clarify.. providing source code would be nice

pukar_giri on 7:04 PM 04/16/2019: just to clarify the problem was easy and i have solved it, i am just trying to learn assembly by recreating source by looking at the assembly which is why i am asking for the source

D4RKFL0W on 8:33 PM 04/17/2019: I can post the source on pastebin or something but not here as think it's a bit to tempting for others to check. But as for not finding an direct c syntax/functions that are assured to compile to a specific instruction. Read a little about the inside logic/steps that a compiler takes.

D4RKFL0W on 8:43 PM 04/17/2019: Don't worry i've just checked the source, its an inline function that just calls strcat multiple times at different pointer offsets. Also just realised it's a C++ binary just to correct myself lol.

sdk_cr on 8:21 AM 04/20/2019: some of the comments are absurd but as long as u find the location u will know cracking is fun. thanks!