Security Analysis of DBTRU Cryptosystem

Xiaofei Tong; Jingguo Bi; Yufei Duan; Lixiang Li; Licheng Wang

doi:10.3390/e24101349

Security Analysis of DBTRU Cryptosystem

Entropy (Basel). 2022 Sep 23;24(10):1349. doi: 10.3390/e24101349.

Authors

Xiaofei Tong^{1

2

3}, Jingguo Bi^{1

3}, Yufei Duan¹, Lixiang Li^{1

2}, Licheng Wang^{1

2}

Affiliations

¹ School of Cyberspace Security, Beijing University of Posts and Telecommunications, Beijing 100876, China.
² State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 100876, China.
³ State Key Laboratory of Cryptology, P.O. Box 5159, Beijing 100878, China.

Abstract

DBTRU was proposed by Thang and Binh in 2015. As a variant of NTRU, the integer polynomial ring is replaced by two binary truncated polynomial rings GF(2)[x]/(xn+1). DBTRU has some advantages over NTRU in terms of security and performance. In this paper, we propose a polynomial-time linear algebra attack against the DBTRU cryptosystem, which can break DBTRU for all recommended parameter choices. The paper shows that the plaintext can be achieved in less than 1 s via the linear algebra attack on a single PC.

Keywords: DBTRU; NTRU; lattice-based attacks; linear algebra attack; public key cryptosystem.

Abstract

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