Related-Key Boomerang and Rectangle Attacks [chapter]

Eli Biham, Orr Dunkelman, Nathan Keller
2005 Lecture Notes in Computer Science  
This paper introduces the related-key boomerang and the related-key rectangle attacks. These new attacks can expand the cryptanalytic toolbox, and can be applied to many block ciphers. The main advantage of these new attacks, is the ability to exploit the related-key model twice. Hence, even ciphers which were considered resistant to either boomerang or related-key differential attacks may be broken using the new techniques. ⋆ This paper is partially based on the papers [9, 10, 27] which
more » ... d at EURO-CRYPT 2005, ASIACRYPT 2005 and FSE 2007, respectively. ⋆⋆ This paper was In this paper we present a rigorous treatment of the related-key boomerang and the related-key rectangle distinguishers. Following this treatment, we devise optimal distinguishing algorithms using the LLR (Logarithmic Likelihood Ratio) statistics. We then analyze the success probability under reasonable independence assumptions, and verify the computation experimentally by implementing an actual attack on a 6-round variant of KASUMI. The paper ends with a demonstration of the strength of our new proposed techniques with attacks on 10-round AES-192 and the full KASUMI.
doi:10.1007/11426639_30 fatcat:lhriavcjofexjjbj46zrxkna6e