< Back to previous page


Cryptanalysis of Dynamic SHA(2)

Book Contribution - Book Chapter Conference Contribution

In this paper, we analyze the hash functions Dynamic SHA and Dynamic SHA2, which have been selected as first round candidates in the NIST hash function competition. These hash functions rely heavily on data-dependent rotations, similar to certain block ciphers, e.g., RC5. Our analysis suggests that in the case of hash functions, where the attacker has more control over the rotations, this approach is less favorable than in block ciphers. We present practical, or close to practical, collision attacks on both Dynamic SHA and Dynamic SHA2. Moreover, we present a preimage attack on Dynamic SHA that is faster than exhaustive search. © 2009 Springer-Verlag Berlin Heidelberg.
Book: Lecture Notes in Computer Science
Pages: 415 - 432
Publication year:2009
Authors from:Higher Education