Cryptanalysis of the Modified Remote Login Authentication Scheme Based on a Geometric Approach

Article type: Research Article

Authors: Chang, Chin‐Chen | Lin, Iuon‐Chang

Affiliations: Department of Computer Science and Information Engineering, National Chung Cheng University, 160, San‐Hsing, Min‐Hsiung, Chiayi 621, Taiwan, e‐mail: ccc@cs.ccu.edu.tw | Department of Management Information System, National Chung Hsing University, 250 Kuo Kuang Road, 402 Taichung, Taiwan, e‐mail: iclin@cs.kuas.edu.tw

Abstract: In 1995, Wu proposed a remote login authentication scheme based on geometric approach. However, Chien, Jan and Tseng presented a cryptanalysis of Wu's scheme to show that it is not secure. Moreover, they proposed a modified version of Wu's scheme. This paper presents there is a serious weakness in this modified remote login authentication scheme. We show that an illegal user can easily forge a valid login request in the modified version proposed previously.

Keywords: cryptography, remote login

Journal: Informatica, vol. 16, no. 1, pp. 37-44, 2005