Quorus: Scalable Threshold ML-DSA from MPC

"Preview Talk" (by Team Quorus) @ MPTS 2026, in reply to the NIST Threshold Call

Abstract. In this presentation, we present an overview of our multi-party key and signature generation protocol for the module-lattice digital signature algorithm (ML-DSA). Our proposal includes an MPC-friendly variant of ML-DSA retaining compatibility with the FIPS 204 compliant verification algorithm, a distributed key generation (DKG) protocol, and an efficient threshold signing protocol with offline preprocessing. Our protocols are designed to provide strong security guarantees, such as post-quantum security and UC security, scalability to medium-sized groups ofsigners (e.g., up to 64) assuming an honest majority, and low signing latency in the online phase.

Joint work: Alexander Bienstock, Leo de Castro, Daniel Escudero, Antigoni Polychroniadou, Akira Takahashi.

[Slides] Suggested readings:

• Preview Writeup: Quorus: Scalable Threshold ML-DSA from MPC
• Efficient, Scalable Threshold ML-DSA Signatures: An MPC Approach (ia.cr/2025/1163)