Abstract
The signature scheme SFLASH has been accepted as candidate in the NESSIE (New European Scheme for Signatures, Integrity, and Encryption) project. We show that recovering the two secret affine map**s F37 2 → F37 2 in SFLASH can easily be reduced to the task of revealing two linear map**s F37 2 → F37 2. In particular, the 74 bits representing these affine parts do by no means contribute a factor of 274 to the effort required for mounting an attack against the system. This raises some doubts about the design of this NESSIE candidate.
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Geiselmann, W., Steinwandt, R., Beth, T. (2001). Attacking the Affine Parts of SFLASH. In: Honary, B. (eds) Cryptography and Coding. Cryptography and Coding 2001. Lecture Notes in Computer Science, vol 2260. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-45325-3_31
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DOI: https://doi.org/10.1007/3-540-45325-3_31
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