Recently, two certificateless three-party authenticated key agreementprotocols were proposed, and both protocols were claimed they can meet thedesirable security properties including forward security, key compromiseimpersonation resistance and so on. Through cryptanalysis, we show that oneneither meets forward security and key compromise impersonation resistance norresists an attack by an adversary who knows all users' secret values, and theother cannot resist key compromise impersonation attack. Finally, we proposeimproved protocols to make up two original protocols' security weaknesses,respectively. Further security analysis shows that our improved protocols canremove such security weaknesses.
展开▼
