Paper 2022/1739
On blindness of several ElGamal-type blind signatures
Abstract
Blind signature schemes are the essential element of many complex information systems such as e-cash and e-voting systems. They should provide two security properties: unforgeability and blindness. The former one is standard for all signature schemes and ensures that a valid signature can be generated only during the interaction with the secret signing key holder. The latter one is more specific for this class of signature schemes and means that there is no way to link a (message, signature) pair to the certain execution of the signing protocol. In the current paper we discuss the blindness property and various security notions formalizing this property. We analyze several ElGamal-type blind signature schemes regarding blindness. We present effective attacks violating blindness on three schemes. All the presented attacks may be performed by any external observer and do not require signing key knowledge. One of the schemes conceivably became broken due to an incorrect understanding of blindness property.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Preprint.
- Keywords
- Blind signature scheme Blindness
- Contact author(s)
- babueva @ cryptopro ru
- History
- 2022-12-19: approved
- 2022-12-19: received
- See all versions
- Short URL
- https://ia.cr/2022/1739
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2022/1739,
author = {Alexandra Babueva and Liliya Akhmetzyanova and Evgeny Alekseev and Oleg Taraskin},
title = {On blindness of several ElGamal-type blind signatures},
howpublished = {Cryptology ePrint Archive, Paper 2022/1739},
year = {2022},
note = {\url{https://eprint.iacr.org/2022/1739}},
url = {https://eprint.iacr.org/2022/1739}
}
