I have written four question for Firebird Internal CTF - Oofbleck (Crypto), Obvious Transfer (Crypto), RC4 (Misc) and Prooof-ooof-Wooork (Reverse, Misc). I will be including all of them in this blog post. Oofbleck (Crypto) One (out of six) team have solved this during the CTF period. Challenge Summary Some of the block cipher modes of operation are pretty vulnerable, which includes but not limited to padding oracle in CBC, key-recovery attacks with repeated nonces in GCM and Zerologon in CFB8.
