Mod Encryption Key New! - Frosty

Decrypt with Python:

Format:

char* get_encryption_key() char *env_key = getenv("FROSTY_KEY"); if (env_key != NULL && strlen(env_key) == 32) return env_key; // Hardcoded fallback key (hex string) return "5f4dcc3b5aa765d61d8327deb882cf99"; frosty mod encryption key

In Ghidra, search for the string "FROSTY_KEY" → cross‑reference to a function get_encryption_key() .

Decompiled pseudocode:

cipher = AES.new(key, AES.MODE_CBC, iv) plaintext = cipher.decrypt(ciphertext) # Remove PKCS#7 padding pad_len = plaintext[-1] return plaintext[:-pad_len] key_hex = "5f4dcc3b5aa765d61d8327deb882cf99" decrypted = decrypt_frosty_config("frosty_config.bin", key_hex) print(decrypted.decode('utf-8'))

[!] Missing encryption key. [+] Key loaded from environment variable FROSTY_KEY. [...] But the challenge states the key is hardcoded – so maybe a fallback exists. frosty mod encryption key

"mod_version": "2.1.0", "author": "FrostyTeam", "flag": "CTFfrosty_mod_3ncrypt10n_k3y_md5_1s_n0t_s3cur3"