Research Papers

Physical attacks (SCA, FIA) threaten crypto hardware. CPC gadgets use the limited CINI model. This work introduces gCINI, a generalized definition. We prove its security and composability, demonstrating a more efficient AES S-box verified via VERICA.

We present the first threshold signature scheme fully compatible with ML-DSA. It is robust, scalable, and optimized for small groups, proving practical for crypto wallets, TLS, and Tor in real-world benchmarks.

PQShield's Lapiha and Prest proposed a lattice-based TKEM from a TIBE and signatures, but with 540 KiB ciphertexts. We optimize it via random oracles, approximate computing, and NTRU trapdoors, reducing ciphertext size 18x to under 30 KiB.

We present the first 3-round (2 online, 1 offline) threshold Schnorr scheme with adaptive security under the DL assumption. By avoiding stronger assumptions like DDH/AOMDL, we close a major gap, achieving efficiency and security from minimal foundations.

To securepost-quantum transition, this paper introduces Hybrid EU-CMA and Silithium. By combining classical and PQ algorithms, Silithium prevents separability attacks while offering faster speeds and smaller sizes than simple concatenation.

Falcon is a post-quantum signature scheme that usually relies on inefficient trial-and-error. This new MCMC sampling method achieves higher security and shorter signatures more efficiently while simplifying the system's overall implementation.

Today marks a massive milestone for Japan’s digital sovereignty. Following PQShield’s comprehensive evaluation of the ML-KEM algorithm for CRYPTREC (Japan’s cryptographic standardization body), the gates are officially open for quantum-safe deployment across the country’s government procurement and technology supply chains.

This is paper is concerned with the theoretical basis of lattice-based cryptography, clarifying how “easy” distinguishing attacks relate to “hard” search attacks used in security proofs.

In this paper, we present a simpler, more efficient way to create a secure, quantum-resistant shared "vault" (a threshold KEM) without using overly complex or slow mathematical tools. It's achieved by combining established cryptographic frameworks with a new, proven mathematical assumption called Coset-Hint-MLWE. The result is a highly secure system that is easier to implement and more practical for real-world use than previous versions.

Recent efforts to transition secure messaging to post-quantum standards, like Apple’s PQ3 and Signal’s updated Triple Ratchet, have introduced complex design trade-offs due to the high communication overhead of post-quantum cryptography. This paper introduces a pragmatic metric and experimental framework to compare these protocols, revealing that no "optimal" protocol exists when balancing security against real-world bandwidth constraints. Additionally, the authors propose a new optimization called "opportunistic sending" and a building block termed "sparse continuous key agreement" to improve protocol efficiency.

We propose a hybrid formal verification approach that combines high-level deductive reasoning and circuit-based reasoning and apply it to highly optimized cryptographic assembly code.