CryptoDB
A Matching Lower Bound on the Minimum Weight of SHA-1 Expansion Code
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Abstract: | Recently, Wang, Yin, and Yu have used a low weight codeword in the SHA-1 message expansion to show a better than brute force method to find collisions in SHA-1. The codeword they used has a (bit) weight of 25 in the last 60 of the 80 expanded words. In this paper we show, using a computer assisted method, that this is indeed the smallest weight codeword. In particular, we show that the minimum weight over GF2 of any non-zero codeword in the SHA-1 (linear) message expansion code, projected on the last 60 words, is at least 25. |
BibTeX
@misc{eprint-2005-12600, title={A Matching Lower Bound on the Minimum Weight of SHA-1 Expansion Code}, booktitle={IACR Eprint archive}, keywords={Hash Functions, Codes, minimum distance}, url={http://eprint.iacr.org/2005/266}, note={ csjutla@us.ibm.com 13008 received 11 Aug 2005, last revised 13 Aug 2005}, author={Charanjit S. Jutla and Anindya C. Patthak}, year=2005 }