Divide-and-Conquer Template Attack on Scloud

Abstract

Since shor proposed the quantum algorithm, the traditional public key cryptosystem is facing the risk of being breached. To address this issue, Post-Quantum Cryptography (PQC), also known as Anti-Quantum Cryptography, has been developed. Among the various PQC techniques, lattice-based cryptography has emerged as a significant area of research due to its many advantages. This paper studies the leakage of post quantum cryptography cloud on physical devices. Discovered that the matrix calculation operation of the Scloud algorithm has an impact on key security. Based on the characteristics of the curve, we propose a divide and conquer template attack method and introduce convolutional neural network technology for template construction. On the Cortex-M3 board, we have demonstrated that the proposed attack can effectively recover the key.