The five-volume set LNCS 15674-15678 constitutes the refereed proceedings of the 28th IACR International Conference on Practice and Theory of Public Key Cryptography, PKC 2025, held in Røros, Norway, during May 1215, 2025. The 60 papers included in these proceedings were carefully reviewed and selected from 199 submissions. They are grouped into these topical sections: MPC and friends; advanced PKE; security of post-quantum signatures; proofs and arguments; multi-signatures; protocols; foundations of lattices and LPN; threshold signatures; isogenies and group actions; secure computation; security against real-world attacks; batch arguments and decentralized encryption; and cryptography for blockchains.
Multi-Signatures: Universally Composable Interactive and Ordered
Multi-Signatures.- Accountable Multi-Signatures with Constant Size Public
Keys.- Privacy-Preserving Multi-Signatures: Generic Techniques and
Constructions Without Pairings.- A Framework for Group Action-Based
Multi-Signatures and Applications to LESS, MEDS, and ALTEQ. Protocols:
Security Analysis of Signals PQXDH Handshake.- Towards Leakage-Resilient
Ratcheted Key Exchange.- Non-Interactive Key Exchange: New Notions, New
Constructions, and Forward Security.- Effcient Verifiable Mixnets from
Lattices, Revisited. Foundations of Lattices and LPN: Vanishing Short Integer
Solution, Revisited: Reductions, Trapdoors, Homomorphic Signatures for
Low-Degree Polynomials.- Discrete Gaussians Modulo Sub-Lattices: New Leftover
Hash Lemmas for Discrete Gaussians.- Memory-Effcient BKW Algorithm for
Solving the LWE Problem.- Worst and Average Case Hardness of Decoding via
Smoothing Bounds.
