Affiliations: Department of Information Management, Chaoyang University of Technology, 168, Gifeng E. Rd., Wufeng, Taichung County, Taiwan 413, ROC, e‐mail: [email protected] | Department of Information Management, National Taichung Institute of Technology, 129 Sec. 3, San‐min Rd., Taichung, Taiwan 404, ROC | Department of Management Information Systems, National Chung Hsing University, 250, Kuo Kuang Road, Taichung, Taiwan 402, ROC
Abstract: In 2001, Hsu et al. proposed a non‐repudiable threshold proxy signature with known signers. In their scheme, the proxy group cannot deny having signed the proxy signature if they did. However, Hsu et al.'s scheme is vulnerable to some attacks. A malicious original signer or malicious proxy signer can impersonate some other proxy signers to generate proxy signatures. In this article, we shall present our cryptanalysis of the Hsu et al.'s scheme. After that, we shall propose a new threshold proxy signature that can overcome the weaknesses.
Keywords: digital signature, proxy signature, threshold proxy signature
Journal: Informatica, vol. 14, no. 3, pp. 393-402, 2003
