reversePromedium

See No Evil - Part 3

ringzer0ctf

Task: reverse a PE32+ Windows binary that hides 5 flags behind per-level anti-debug gates, extract Part 3's flag. Solution: statically recover the level-3 magic constant and ciphertext, derive the DES key as MD5(magic)[:8] and DES-ECB decrypt the blob.

des windows md5 multi_level reverse anti_debug cryptoapi pe32plus int3_handler create_thread_guard dispatch_table

static_flag_extractiondispatch_table_recoverydes_ecb_decryptpointer_table_recoverymd5_des_key_derivationimpdb_symbol_recovery

$ ls tags/ techniques/

des windows md5 multi_level reverse anti_debug cryptoapi pe32plus int3_handler create_thread_guard dispatch_table

static_flag_extractiondispatch_table_recoverydes_ecb_decryptpointer_table_recoverymd5_des_key_derivationimpdb_symbol_recovery

Analysis

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

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