Paper 2020/1172
Cryptanalysis of a round optimal lattice-based multisignature scheme
Zi-Yuan Liu, Yi-Fan Tseng, and Raylin Tso
Abstract
Kansal and Dutta recently proposed a multisignature scheme at AFRICACRYPT 2020. This is the first lattice-based multisignature scheme that generates a multisignature in only a single round of interaction and supports public key aggregation. In this letter, we provide a cryptanalysis of this multisignature scheme and demonstrate that the scheme does not satisfy unforgeability requirements. We present an attack strategy to demonstrate that if an adversary obtains a sufficient number of signatures from a signer, he/she can recover the private key of the signer in polynomial time. We also uncover the root cause of the attack and provide a possible solution for this attack to aid future designs of secure multisignature schemes.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Preprint. MINOR revision.
- Keywords
- CryptanalysisMultisignatureLatticesUnforgeability
- Contact author(s)
- zyliu @ cs nccu edu tw
- History
- 2020-09-25: received
- Short URL
- https://ia.cr/2020/1172
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2020/1172,
author = {Zi-Yuan Liu and Yi-Fan Tseng and Raylin Tso},
title = {Cryptanalysis of a round optimal lattice-based multisignature scheme},
howpublished = {Cryptology {ePrint} Archive, Paper 2020/1172},
year = {2020},
url = {https://eprint.iacr.org/2020/1172}
}
