Cryptanalysis of ring-LWE based key exchange with key share reuse

Scott Fluhrer

Paper 2016/085

Cryptanalysis of ring-LWE based key exchange with key share reuse

Scott Fluhrer

Abstract

This paper shows how several ring-LWE based key exchange protocols can be broken, under the assumption that the same key share is used for multiple exchanges. This indicates that, if these key exchange protocols are used, then it will be necessary for a fresh key share be generated for each exchange, and that these key exchange protocols cannot be used as a drop in replacement for designs which use Diffie-Hellman static key shares.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Preprint. MINOR revision.
Keywords: lattice techniques LWE ring LWE
Contact author(s): sfluhrer @ cisco com
History: 2016-01-31: received
Short URL: https://ia.cr/2016/085
License: CC BY

BibTeX

@misc{cryptoeprint:2016/085,
      author = {Scott Fluhrer},
      title = {Cryptanalysis of ring-{LWE} based key exchange with key share reuse},
      howpublished = {Cryptology {ePrint} Archive, Paper 2016/085},
      year = {2016},
      url = {https://eprint.iacr.org/2016/085}
}