Author:
0xbabe

Language:
C/C++

Upload:
10:42 AM 12/04/2023

Download

Platform
Windows

Difficulty:
3.0

Quality:
3.0

Arch:
x86-64

Description

As always, it doesn't have any anti debug checks. The code is running under virtual machine and not packed. What you have to do? - Find a password (EZ LVL) - Patch the program to accept any password (HARD LVL)

• Comments
• Solutions

dev0 on 10:59 AM 12/07/2023: Opcode 3 is a NOP. Would you accept a NOP sled to the two bytecode instructions (Opcode 0 loading the strings) that loads to the two registers with the "Good password!" message and VM name? At that point the user would never even need to enter anything and the correct message would output.

0xbabe on 3:26 PM 12/07/2023: There's no opcodes for NOP. The task is patch the program to accept any program, so your way is wrong.

ReverseLabs on 1:39 AM 12/09/2023: Would it count as a patch if I just NOP ds:[00007FF74BD13420]: "Bad password!" the output is "Good password!" so it kinda works.

sporta778 on 11:57 AM 12/11/2023: solution in studio!

sporta778 on 3:42 PM 12/11/2023: it's easy in offset of file u need 0x449 patch byte to 0xc4 and programm will always show good password, but i do not understand what is correct password.. i do not understand how it compare to correct password....

sporta778 on 4:04 PM 12/11/2023: mistake offset is 0x448

NopNopNop on 1:32 PM 12/19/2023: Password 4099 or 0x1003 in hex.Instruction to patch is jne to jmp at RVA:0x14A0

blockslesson on 7:11 PM 01/09/2024: 1 - the password is '4099' any pass path : in 0x147F change rdx to rcx

sporta778 on 9:10 PM 04/27/2024: I send solution, i am too I'm in a hurry. Here present uniformity with VM

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