A Security Patch for a Three-Party Key Exchange Protocol  

作　　者：ZHAO Jianjie GU Dawu 

机构地区：[1]School of Information Security Engineering, Shanghai Jiao Tong University, Shanghai 200240, China [2]Department of Computer Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China

出　　处：《Wuhan University Journal of Natural Sciences》2010年第3期242-246,共5页武汉大学学报（自然科学英文版）

基　　金：Supported by the National High Technology Research and Development Program of China (863 Program)(2006AA01Z405)

摘　　要：The CLC protocol （proposed by Tzung-Her Chen, Wei-Bin Lee and Hsing-Bai Chen, CLC, for short） is a new three-party password-authenticated key exchange （3PAKE） protocol. This CLC protocol provides a superior round efficiency （only three rounds）, and its resources required for computation are relatively few. However, we find that the leakage of values VA and VB in the CLC protocol will make a man-in-the-middle attack feasible in practice, where VA and VB are the authentication information chosen by the server for the participants A and B. In this paper, we describe our attack on the CLC protocol and further present a modified 3PAKE protocol, which is essentially an improved CLC protocol. Our protocol can resist attacks available, including man-in-the-middle attack we mount on the initial CLC protocol. Meanwhile, we allow that the participants choose their own pass- words by themselves, thus avoiding the danger that the server is controlled in the initialization phase. Also, the computational cost of our protocol is lower than that of the CLC protocol.The CLC protocol （proposed by Tzung-Her Chen, Wei-Bin Lee and Hsing-Bai Chen, CLC, for short） is a new three-party password-authenticated key exchange （3PAKE） protocol. This CLC protocol provides a superior round efficiency （only three rounds）, and its resources required for computation are relatively few. However, we find that the leakage of values VA and VB in the CLC protocol will make a man-in-the-middle attack feasible in practice, where VA and VB are the authentication information chosen by the server for the participants A and B. In this paper, we describe our attack on the CLC protocol and further present a modified 3PAKE protocol, which is essentially an improved CLC protocol. Our protocol can resist attacks available, including man-in-the-middle attack we mount on the initial CLC protocol. Meanwhile, we allow that the participants choose their own pass- words by themselves, thus avoiding the danger that the server is controlled in the initialization phase. Also, the computational cost of our protocol is lower than that of the CLC protocol.

关 键 词：information security AUTHENTICATION key exchange man-in-the-middle attack 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]