Lacks's Level 7

Author:
Lacks

Language:
C/C++

Upload:
2026-07-10 17:24

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Platform:
Windows

Difficulty:
4.0

Quality:
4.0

Arch:
x86-64

Downloads:
165

Size:
22.00 KB

Writeups:
1

Comments:
6

Description

This is level 7 im uploading 1 - 10 crack mes

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Comments (6)
Writeups (1)

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dandelion_msla on 2026-07-13 00:52: Thanks! found the license ;)

Lover1500 on 2026-07-13 14:48: [Click to reveal]

Toji on 2026-07-14 20:32: [Click to reveal]

Phantaso on 2026-07-21 15:19: 0x36 ^ 0x5A = 0x6C -> l 0x33 ^ 0x5A = 0x69 -> i 0x39 ^ 0x5A = 0x63 -> c 0x3F ^ 0x5A = 0x65 -> e 0x34 ^ 0x5A = 0x6E -> n 0x29 ^ 0x5A = 0x73 -> s 0x3F ^ 0x5A = 0x65 -> e

kotsuge on 2026-07-21 21:30: [Click to reveal]

ludzof on 2026-07-28 22:38: This level hides a "Secret Menu" behind a perfectly designed XOR check! Here is the breakdown: The Check: The program takes your input and explicitly checks it character-by-character against a hidden string in memory. However, the hidden string is XORed with 0x5A. By dumping the memory at the pointer 7FF675E37230, we find the raw bytes: 36 33 39 3F 34 29 3F. Reversing the XOR (0x36 ^ 0x5A, etc.), we get the exact password: license The Easter Egg: The program also calculates an XOR key by taking the sum of the password characters modulo 256 (0xE3), and XORing that with 0xA5 (which equals 0x46). It uses this key to decrypt the garbage header. If you enter license, it perfectly decrypts the header to say: Welcome to the Secret Menu!

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Solution by MoriartyPuth on 2026-07-15 18:20:

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crackmes.one

crackmes.one

Lacks's Level 7