Paper 2017/1069
Non-Malleability vs. CCA-Security: The Case of Commitments
Brandon Broadnax, Valerie Fetzer, Jörn Müller-Quade, and Andy Rupp
Abstract
In this work, we settle the relations among a variety of security notions related to non-malleability and CCA-security that have been proposed for commitment schemes in the literature. Interestingly, all our separations follow from two generic transformations. Given two appropriate security notions X and Y from the class of security notions we compare, these transformations take a commitment scheme that fulfills notion X and output a commitment scheme that still fulfills notion X but not notion Y. Using these transformations, we are able to show that some of the known relations for public-key encryption do not carry over to commitments. In particular, we show that, surprisingly, parallel non-malleability and parallel CCA-security are not equivalent for commitment schemes. This stands in contrast to the situation for public-key encryption where these two notions are equivalent as shown by Bellare et al. at CRYPTO ‘99.
Metadata
- Available format(s)
-
PDF
- Publication info
- Published by the IACR in PKC 2018
- Keywords
- non-malleabilityCCA securitycommitmentssecurity definitions
- Contact author(s)
- brandon broadnax @ kit edu
- History
- 2018-01-09: revised
- 2017-11-10: received
- See all versions
- Short URL
- https://ia.cr/2017/1069
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2017/1069,
author = {Brandon Broadnax and Valerie Fetzer and Jörn Müller-Quade and Andy Rupp},
title = {Non-Malleability vs. {CCA}-Security: The Case of Commitments},
howpublished = {Cryptology {ePrint} Archive, Paper 2017/1069},
year = {2017},
url = {https://eprint.iacr.org/2017/1069}
}
