Preimages for Step-Reduced SHA-2

Jian Guo; Krystian Matusiewicz

Paper 2009/477 Original: eprint.iacr.org/2009/477 ↗

Preimages for Step-Reduced SHA-2

Jian Guo

Krystian Matusiewicz

Abstract

In this paper, we present a preimage attack for 42 step-reduced SHA-256 with time complexity $2^{251.7}$ and memory requirements of order $2^{12}$. The same attack also applies to 42 step-reduced SHA-512 with time complexity $2^{502.3}$ and memory requirements of order $2^{22}$. Our attack is meet-in-the-middle preimage attack.

Metadata

Available format(s): PDF
Category: Secret-key cryptography
Publication info: Preprint.
History: 2009-10-01: last updated; 2009-09-29: published
Short URL: https://ia.cr/2009/477
License: https://creativecommons.org/licenses/by/4.0/

BibTeX

@misc{cryptoeprint:2009/477,
      author = {Jian Guo and Krystian Matusiewicz},
      title = {Preimages for Step-Reduced SHA-2},
      howpublished = {Cryptology {ePrint} Archive, Paper 2009/477},
      year = {2009},
      url = {https://eprint.iacr.org/2009/477}
}