downloadbrowseH2SO4's CrackMe1

Download, 206 kb (password:
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This a username/serial crackme.
No anti-debug tricks...


- Don't patch the exe. Just find the algo.
- If you found it, write a keygen.
- And if you are still not satisfied, write a nice tutorial!

Hope you enjoy!

Difficulty: 1 - Very easy, for newbies
Platform: Windows
Language: .NET

Published: 16. Oct, 2010
Downloads: 980


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Solution by ZaZa, published 14. jun, 2012; download (30 kb), password: or browse.

ZaZa has rated this crackme as boring.

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Discussion and comments

20. Oct 2010
For some reason crackme crashes every time i try to run it, tried to run it on w7, xp with .net 4.0 installed, crashes always. But anyway, keygen is done by static analysis:


should work :>
20. Oct 2010
@tamaroth: Indeed! It works, Good job! Strange about the crashing program. Can you write a tutorial. I'm unable to crack it: the .NET Framework hides all my constants, strings, ...
28. Dec 2010
crackme crashes every time for me too
15. Jun 2012
I also encountered an error: overflow of an arithmetic operation.
This was associated with the following line: Dim num7 As Integer = (((num3 * num5) Mod & H6A) + num4). num5 is SByte, as num3 ... When multiplying, the type of temporary defines an intermediate variable as SByte, that can not get into the border ... Therefore, a mistake!

To resolve this error, change the line to: Dim num7 As Integer = (((Cint (num3) * Cint (num5)) Mod & H6A) + num4)

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