International Association for Cryptologic Research

International Association
for Cryptologic Research


Paper: On Security Notions for Verifiable Encrypted Signature

Xu-An Wang
Xiaoyuan Yang
Yiliang Han
Search ePrint
Search Google
Abstract: First we revisit three - BGLS, MBGLS and GZZ verifiably encrypted signature schemes[2,3,6].We find that they are all not strong unforgeable.We remark that the notion of existential unforgeable is not sufficient for fair exchange protocols in most circumstances.So we propose three new - NBGLS, MBGLS and NGZZ verifiably encrypted signature schemes which are strong unforgeable. Also we reconsider other two - ZSS and CA verifiably encrypted signature schemes[4,8], we find that they both cannot resist replacing public key attack. So we strongly suggest that strong unforgeable for verifiably encrypted signature maybe a better notion than existential unforgeable and checking adjudicator knowing its private key is a necessary step for secure verifiably encrypted signature scheme.
  title={On Security Notions for Verifiable Encrypted Signature},
  booktitle={IACR Eprint archive},
  keywords={public-key cryptography /},
  note={ 14020 received 3 Mar 2008, last revised 21 May 2008},
  author={Xu-An Wang and Xiaoyuan Yang and Yiliang Han},