cryptoProeasy

babyCrypto

grsu

Task: Recover 3-byte HMAC salt from 128 message/MAC pairs. Solution: Brute-force the small salt space with early filtering, then XOR-decrypt the flag.

$ ls tags/ techniques/

sha256 bruteforce xor hmac mac

xor_decryptionsalt_bruteforcehmac_verification

Analysis

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$ python3 exploit.py --target 192.168.1.1 --port 8080
[*] Connecting to target...
[+] Shell obtained!

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