Near-Collisions for the Reduced Round Versions of Some Second Round SHA-3 Compression Functions Using Hill Climbing

Turan M. S., Uyan E.

11th International Conference on Cryptology in India, Hyderabad, Pakistan, 12 - 15 December 2010, vol.6498, pp.131-133 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 6498
  • City: Hyderabad
  • Country: Pakistan
  • Page Numbers: pp.131-133
  • Middle East Technical University Affiliated: Yes


A hash function is near-collision resistant, if it is hard to find two messages with hash values that differ in only a small number of bits. In this study, we use hill climbing methods to evaluate the near-collision resistance of some of the second round SHA-3 candidates. We practically obtained (i) 184/256-bit near-collision for the 2-round compression function of Blake-32; (ii) 192/256-bit near-collision for the 2-round compression function of Hamsi-256; (iii) 820/1024-bit near-collisions for 10-round compression function of JH. Among the 130 possible reduced variants of Fugue-256, we practically observed collisions for 7 variants (e.g. (k, r, t) = (1, 2,5)) and near-collisions for 26 variants (e.g. 234/256 bit near-collision for (k, r, t) = (2,1,8)).