Paper 2026/2818

Round-Optimal Statistical Verifiable Secret Sharing with Polynomial Complexity

Chen-Da Liu-Zhang, Lucerne University of Applied Sciences and Arts
Elisaweta Masserova, Carnegie Mellon University
Abstract

Verifiable secret sharing (Chor, Goldwasser, Micali, and Awerbuch; FOCS'85) is a central primitive in secure computation, and its round complexity has been studied extensively. Rabin and Ben-Or [STOC'89] established the feasibility of statistical security up to $t<n/2$ corruptions, and Patra, Choudhary, Rabin, and Rangan [Crypto'09] showed that three sharing rounds are necessary. The work of Applebaum, Kachlon and Patra [STOC'23] introduced the first round-optimal VSS with three rounds of sharing and one round for reconstruction, albeit with exponential communication in the number of parties. We give the first round-optimal statistical VSS that has polynomial communication and computation for $t<n/2$. This resolves the efficiency question left open by Applebaum, Kachlon and Patra. The protocol is obtained from a new notion of weak secret sharing, in which the reconstruction-time freedom of a corrupt dealer is limited to choosing verification keys, which is of independent interest.

Metadata
Available format(s)
PDF
Category
Cryptographic protocols
Publication info
Preprint.
Keywords
VSSMPCstatistical security
Contact author(s)
chendaliu @ gmail com
elisawem @ andrew cmu edu
History
2026-11-10: approved
2026-11-07: received
See all versions
Short URL
https://ia.cr/2026/2818
License
Creative Commons Attribution
CC BY

BibTeX

@misc{cryptoeprint:2026/2818,
      author = {Chen-Da Liu-Zhang and Elisaweta Masserova},
      title = {Round-Optimal Statistical Verifiable Secret Sharing with Polynomial Complexity},
      howpublished = {Cryptology {ePrint} Archive, Paper 2026/2818},
      year = {2026},
      url = {https://eprint.iacr.org/2026/2818}
}
Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.