Cryptanalysis of efficient threshold proxy signature protocol for mobile agents

摘要

An efficient threshold proxy signature protocol for mobile agents based on RSA cryptosystem [Information Sciences 179 (2009) 4243–4248] was proposed. We analyze its security and show that the original signer can generate a valid proxy signature by himself. In addition, nobody can discriminate the identities of the actual proxy signers. Therefore, this protocol does not satisfy the properties of unforgeability and identifiability for proxy signature.