On a lattice-based post-quantum ring signature scheme

Journal of Computer Virology and Hacking Techniques. 2026. No. 22.

Kuninets A., Malygina E., Nesterenko A., Kurochkin A. V.

This work describes a post-quantum lattice-based linkable ring signature scheme over NTRU lattices, constructed within the Raptor framework. Our design incorporates the Ducas–Prest Gaussian sampler, the signature generation and verification algorithms from the Falcon scheme, and the key generation algorithm from the Mitaka scheme. This hybrid approach combines Falcon’s compact signatures and fast verification with Mitaka’s efficient key generation and enhanced resistance to side-channel attacks. We obtain our scheme by adapting Falcon’s signing and verification procedures to operate with the Ducas–Prest sampler and Mitaka-style trapdoor generation. This yields a construction that maintains competitive performance for small ring sizes while avoiding floating-point arithmetic, making it more suitable for constrained or embedded platforms. The resulting scheme leverages the advantages of the original Raptor framework and the Mitaka scheme, offering a favorable balance between signature size, verification speed, and computational complexity, while enabling instantiation over a wide range of cyclotomic parameters. An additional feature of the proposed ring signature is the ability to choose an arbitrary number of ring members. Moreover, for the small ring sizes required in most blockchain applications, we achieve public key and signature sizes comparable to other lattice-based ring signatures that do not allow such flexibility in the number of ring members. Finally, we discuss signature applicability in privacy-focused blockchain protocols such as Monero, where linkable ring signatures enable unlinkability and accountability, and in confidential asset systems, where multi-asset transaction integrity and anonymity must be preserved.

Keywords: blockchain technology, блокчейн-технологии, постквантовая криптография, post-quantum cryptography, lattice-based cryptography, linkable ring signatures, связываемые кольцевые подписи, криптография на решётках