Paper 2025/599 Original: eprint.iacr.org/2025/599 ↗

Insecurity of One Decentralized Attribute-based Signature Scheme for Social Co-governance

Abstract

We show that the attribute-based signature scheme [Information Sciences, 654(2024), 119839] is insecure, because an adversary can generate valid signatures for any message even though he cannot access the signer's secret key. The four components of signature $\{\delta_1, \delta_2, \delta_3, \delta_4\}$ are not tightly bound to the target message $M$ and the signer's public key. The dependency between the signer's public key and secret key is not properly used to construct any intractable problem. The inherent flaw results in that the adversary can find an efficient signing algorithm functionally equivalent to the valid signing algorithm.