Paper 2026/1603 Original: eprint.iacr.org/2026/1603 ↗
Design and Analysis of Quantum Designated Verifier Signature Scheme
Abstract
Designated Verifier Signatures (DVS) are an important variant of digital signatures that ensure only a specified verifier can validate a signature, while preserving non-transferability. With the advent of quantum computing, several quantum DVS schemes have been proposed to achieve quantum security. In this paper, we revisit the quantum DVS protocol of Xin et al. [Quantum Information Processing, 2022] and provide a structural cryptanalysis of its design. We show that the scheme admits an existential forgery under a chosen-message attack: given a valid quantum signature on one message, an adversary can efficiently transform it into a valid signature on another message without knowledge of the signer’s private key. To address this weakness, we propose a minimal countermeasure based on QKD-derived keys and quantum one-time pad encryption.
Metadata
- Available format(s)
PDF- Category
- Attacks and cryptanalysis
- Publication info
- Preprint.
- History
- 2026-08-04: last updated
- 2026-08-04: published
- Short URL
- https://ia.cr/2026/1603
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2026/1603,
author = {Shanu Poddar and Vikas Srivastava},
title = {Design and Analysis of Quantum Designated Verifier Signature Scheme},
howpublished = {Cryptology {ePrint} Archive, Paper 2026/1603},
year = {2026},
url = {https://eprint.iacr.org/2026/1603}
}