An Improved Digital Signature with Message Recovery Using Self-certified Public Keys Without Trustworthy System Authority

摘要

In 2005, Chang et al. proposed a digital signature scheme with message recovery using self-certified public keys without trustworthy system authority. The current paper demonstrates that Chang et al.'s authenticated encryption scheme (CCH-AEDSMR) is vulnerable to the known plaintext-ciphertext attack in that the attacker can easily recover all messages from the signature that sent between the signer and the specified receiver. We propose an improvement to the scheme in order to overcome this weakness.