Simple Power Analysis of Polynomial Multiplication in HQC

TL;DR

This paper demonstrates a successful single-trace Simple Power Analysis attack on the HQC cryptosystem's polynomial multiplication, revealing vulnerabilities and proposing countermeasures to enhance security.

Contribution

It introduces the first SPA attack on HQC's polynomial multiplication and evaluates effective countermeasures, advancing understanding of side-channel vulnerabilities in PQC algorithms.

Findings

Achieved 99.69% success rate in attack

Identified vulnerabilities during polynomial multiplication

Proposed and evaluated countermeasures

Abstract

The Hamming Quasi-Cyclic (HQC) cryptosystem was selected for standardization in the fourth round of the NIST Post-Quantum Cryptography (PQC) standardization project. The goal of the PQC project is to standardize one or more quantum-resistant public-key cryptographic algorithms. In this paper, we present a single-trace Simple Power Analysis (SPA) attack against HQC that exploits power consumption leakage that occurs during polynomial multiplication performed at the beginning of HQC decryption. Using the ChipWhisperer-Lite board, we perform and evaluate the attack, achieving a 99.69% success rate over 10 000 attack attempts. We also propose various countermeasures against the attack and evaluate their time complexity.