On the Security of LWE Cryptosystem against Subversion Attacks. (10th September 2019)

• Record Type: Journal Article
• Authors: Yang, Zhichao; Chen, Rongmao; Li, Chao; Qu, Longjiang; Yang, Guomin
• Is Part Of: Computer journal. Volume 63:Number 4(2020)
• Page Start: 495
• Page End: 507
• Publication Date: 2019-09-10
• Subjects: Public Key -- Subversion Attack -- Post-Quantum -- Lattice; Computers -- Periodicals; 005.1
• DOI: 10.1093/comjnl/bxz084
• Languages: English
• ISSNs: 0010-4620

Abstract

Abstract: Subversion of cryptography has received wide attentions especially after the Snowden Revelations in 2013. Most of the currently proposed subversion attacks essentially rely on the freedom of randomness choosing in the cryptographic protocol to hide backdoors embedded in the cryptosystems. Despite the fact that significant progresses in this line of research have been made, most of them mainly considered the classical setting, while the research gap regarding subversion attacks against post-quantum cryptography remains tremendous. Inspired by this observation, we investigate a subversion attack against existing protocol that is proved post-quantum secure. Particularly, we show an efficient way to undetectably subvert the well-known lattice-based encryption scheme proposed by Regev (STOC 2005). Our subversion enables the subverted algorithm to stealthily leak arbitrary messages to the outsider who knows the backdoor. Through theoretical analysis and experimental observations, we demonstrate that the subversion attack against the LWE encryption scheme is feasible and practical.