downloadbrowseOffice Jesus's Fun KeygenMe #2

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Here's a simple crypto keygenme.

1) Keygen + Tutorial is the ultimate goal
2) Self-Keygenning and Phishing are more than welcome
3) Patching is acceptable as a last resort

Please report any bugs...

Good luck,

Difficulty: 3 - Getting harder
Platform: Windows
Language: Assembler

Published: 14. Jan, 2015
Downloads: 467


Votes: 3
Crackme is nothing special.

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Solution by chalter, published 08. feb, 2015; download (25 kb), password: or browse.

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Discussion and comments

15. Jan 2015
Hey bro, where is Fun KeygenMe#1? :)
18. Jan 2015
This is a nice keygenme
but i have solved it by T4you on 03 Jan
28. Jan 2015
The modular exponentiation algorithm starting at 405380 was funky to work through and understand how it works. Very weird way of exponentiation! Is there a name for the algorithm or did you work it out yourself to obscure it?
28. Jan 2015
Does this require one to know SHA-1 or no?
Office Jesus
29. Jan 2015
@Coderess: That one I don't think is worthy of posting here. I don't like it as much as this one.

@chalter: This uses drizz's library for the modular arithmetic. If you want to know more about that particular implementation, he has documentation available... somewhere. I designed everything else _outside_ the library, and nothing was obscured too heavily. I'm sure someone will provide a tutorial explaining how everything works. You can also message me for more information.

@Herz3h: You don't need to know _how_ SHA-1 works as long as you know what it is and can recognize it.
03. Feb 2015
I liked how you've hardcoded part of the serial as a discrete log.

Thanks for fun kgme!
04. Feb 2015
I can say I've done it, and learned alot of how RSA work in a process. Its a shame how little I know about this the most important crypto today. Thanks!
25. Feb 2015
Wow i just read the solution, no way i could have solved it......

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