alpjs's custom vmp crackme

Author:
alpjs

Language:
C/C++

Upload:
2026-09-12 02:20

Download

Platform:
Windows

Difficulty:
2.0

Quality:
4.0

Arch:
x86-64

Downloads:
145

Size:
49.50 KB

Writeups:
0

Comments:
13

Description

VMP-style VM around a simple password check. Password runs through a runtime-decrypted, shuffle-per-run bytecode VM + sponge keystretcher/MAC. Anti-debug (PEB, 0xCC, DRx, timing, window scan), PatchGuard checksum self-check — patching poisons the key path. No packer. Find the password, don't patch it.

Labels ?

Anti-debugging Timing (rdtsc/GetTickCount) PEB BeingDebugged / NtGlobalFlag INT3 / 0xCC breakpoint scan Hardware breakpoints (DRx) NtQueryInformationProcess String / data encryption XOR Self-modifying / runtime decrypt Crypto / hash algorithm Code virtualization / VM Control-flow obfuscation Indirect / computed jumps & calls Anti-disassembly Junk / garbage bytes Import / API obfuscation Custom / generic obfuscation

Comments (13)
Writeups (0)

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kotsuge on 2026-09-12 13:37: custom vmp? its custom packer.

alpjs on 2026-09-12 13:58: ...

maureene14 on 2026-09-12 14:29: hello world!

alpjs on 2026-09-12 19:28: You seem to be struggling.

unknownuser1 on 2026-09-12 20:04: [Click to reveal]

alpjs on 2026-09-12 20:06: nice Could you write up a proper report?

unknownuser1 on 2026-09-12 20:12: [Click to reveal]

alpjs on 2026-09-12 20:15: How difficult was it?

unknownuser1 on 2026-09-12 20:16: to be honest it wasnt a 2/10 id say it was more like a 4/10+

alpjs on 2026-09-12 21:19: How many minutes did it take?

lexx on 2026-09-13 07:15: So did you need to find the flag? The task says to find the password

alpjs on 2026-09-13 12:51: The goal is to find the correct password and obtain the flag.

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crackmes.one

alpjs's custom vmp crackme