A Note on the Blindness of the Scheme from ePrint 2025/397

Lucjan Hanzlik

Paper 2025/425

A Note on the Blindness of the Scheme from ePrint 2025/397

Lucjan Hanzlik

, CISPA Helmholtz Center for Information Security

Abstract

This note demonstrates that the blind signature scheme based on cryptographic group actions, as proposed in ePrint paper 2025/397, fails to ensure blindness. Specifically, we construct an adversary that achieves a $1/8$ advantage in the blindness experiment. The attack leverages selective abort techniques (also known as selective failure attacks), a well-known strategy in the MPC literature.

Metadata

Available format(s): PDF
Category: Attacks and cryptanalysis
Publication info: Preprint.
Keywords: blind signatures eprint 2025/397 group actions blindness
Contact author(s): hanzlik @ cispa de
History: 2025-03-05: approved; 2025-03-05: received; See all versions
Short URL: https://ia.cr/2025/425
License: CC0

BibTeX

@misc{cryptoeprint:2025/425,
      author = {Lucjan Hanzlik},
      title = {A Note on the Blindness of the Scheme from {ePrint} 2025/397},
      howpublished = {Cryptology {ePrint} Archive, Paper 2025/425},
      year = {2025},
      url = {https://eprint.iacr.org/2025/425}
}