Paper 2026/1928 Original: eprint.iacr.org/2026/1928 ↗
Two-Round Threshold Signatures with Adaptive TS-UF-1 Security from MDDH
Abstract
In this paper, we construct threshold signatures (TS) to achieve adaptive TS-UF-1 security and identifiable abort. Our TS construction has two rounds. We prove its adaptive TS-UF-1 security in the random oracle model (ROM) under the MDDH (covering DDH) assumption in pairing-free groups. To the best of our knowledge, there are only two TS schemes, namely GLRS26 (Gerhart et al., Eurocrypt 2026) and Dazzle (Chen, PKC 2025), enjoying two rounds, identifiable abort and adaptive security from DDH in pairing-free groups in the ROM. However, both schemes only achieve adaptive TS-UF-0 security. Therefore, our construction yields the first TS scheme enjoying adaptive TS-UF-1 security and identifiable abort, free of pairing.
Metadata
- Available format(s)
PDF- Category
- Public-key cryptography
- Publication info
- Preprint.
- History
- 2026-09-08: last updated
- 2026-09-08: published
- Short URL
- https://ia.cr/2026/1928
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2026/1928,
author = {Wenzhong Li and Shengli Liu and You Lyu},
title = {Two-Round Threshold Signatures with Adaptive TS-UF-1 Security from MDDH},
howpublished = {Cryptology {ePrint} Archive, Paper 2026/1928},
year = {2026},
url = {https://eprint.iacr.org/2026/1928}
}