Alex Biryukov is a cryptographer, currently an associate professor at the University of Luxembourg. His notable work includes the design of the stream cipher LEX, as well as the cryptanalysis of numerous cryptographic primitives. In 1998, he developed impossible differential cryptanalysis together with Eli Biham and Adi Shamir. In 1999, he developed the slide attack together with David Wagner. In 2009 he developed, together with Dmitry Khovratovich, the first cryptanalytic attack on full-round AES-192 and AES-256 that is faster than a brute-force attack.