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

Turan, Meltem Soenmez
Uyan, Erdener
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)).


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Citation Formats
M. S. Turan and E. Uyan, “Near-Collisions for the Reduced Round Versions of Some Second Round SHA-3 Compression Functions Using Hill Climbing,” Hyderabad, India, 2010, vol. 6498, p. 131, Accessed: 00, 2020. [Online]. Available: