Cryptanalysis of a Threshold Proxy Signature Scheme∗
نویسندگان
چکیده
A (t, n) threshold proxy signature scheme allows t or more proxy signers out of a designated group of n proxy signers to sign messages on behalf of an original signer. Recently, Hwang et al. proposed a new (t, n) threshold proxy signature scheme based on the RSA cryptosystem. In this paper, we show that their scheme is insecure against the original signer’s forgery and the general forgery.
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