Difficulty :                   5
Language :                 Borland Delphi
Platform :                   Windows x32
OS Version :              Windows XP +
Packer / Protector : VMProtect v 3.x

Description : enter password

Screenshot :

123.exe

So you spam people to do the job for you and simultaneusly post the thing as a challenge?
Ok. You know what? Whatever

Login pass: 65412312345
Attached is the ripped algorithm of the generator, I'm throwing this one in for free for sh*t and giggles.

src.7z

Edited October 14, 20177 yr by SmilingWolf

Why VMProtected? is your algo to simply that you must protect it?

 

SmilingWolf

  Thank you very much) please forgive me

11 hours ago, ragdog said:

Why VMProtected? is your algo to simply that you must protect it?

Simple is quite the understatement. 11 lines in asm, and IDA sums it up nicely as:

unsigned int __stdcall Generate(unsigned int inputNum)
{
  return 234567891 * __ROL4__(123456791 * (inputNum ^ 0xABD13D59), 16) % 100000000u;
}

Also, it's neither his algorithm nor a challenge created by him. It came into my inbox as a crack request.

It was a Joke

Oh, wonderful.

I thought VMProtect 3.x is perfect packer for Anti-Reversing.

But SmilingWolf changed my concept.

How did you unpacked VMProtec 3.x easily like this?

I am a beginner of reversing. Please post good article about the VMProtect newest versions.

On 6/11/2017 at 2:59 PM, LiuXing said:

Oh, wonderful.

I thought VMProtect 3.x is perfect packer for Anti-Reversing.

 

VMProtect can be powerful if used properly.

Which implies using virtualized sections of code inside the application, something which this program's author blatantly failed to do.
By the way, I didn't unpack the program. I only had to get around VMProtect's anti debugging (easy with ScyllaHide's preset) and debug it to retrieve both the password and the algorithm.

As a pure packer it's meh IMO. Then again, that's not its main purpose, as the name suggests. It is a really interesting virtualizer.

Edited November 10, 20177 yr by SmilingWolf