College of Computer and Information Engineering, Hohai University, Nanjing, P.R.China, 210098

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Abstract—In this paper, we first propose the definition and security model of certificate-based proxy signature (CBPS). We then show that the certificate-based proxy signature scheme presented by Kang, Park and Hahn in CT-RSA 2004 are insecure against key replacement attacks. We further propose two certificate-based proxy signature schemes, which are shown to be existentially unforgeable against adaptive chosen message attacks under the computational Diffie-Hellman assumption in the random oracle model. Compared with the certificate-based proxy signature scheme in CT-RSA 2004, one of our schemes enjoys the same signature length and computation cost, another one requires a little more computation and communication cost.

Index Terms—Certificate-based signature; proxy signature; key replacement attack.

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Cite: Jiguo Li, Lizhong Xu, Yichen Zhang, "Provably Secure Certificate-based Proxy Signature Schemes," Journal of Computers vol. 4, no. 6, pp. 444-452, 2009.