Forgery attacks on Kang et al.'s identity-based strong designated verifier signature scheme and its improvement with security proof

Ji Seon Lee, Jik Hyun Chang, Dong Hoon Lee

Research output: Contribution to journalArticlepeer-review

31 Citations (Scopus)


Recently, Kang et al. proposed a new identity-based strong designated verifier signature scheme (ID-SDVS) and identity-based designated verifier proxy signature scheme (ID-DVPS). They claimed that their schemes are unforgeable. However, we found out that their schemes are universally forgeable in the sense that anyone can forge valid ID-SDVS and ID-DVPS on an arbitrary message without the knowledge of the secret key of either the signer or the designated verifier. Finally, we propose an improved ID-SDVS which is unforgeable. We give formal security proof of universal unforgeability of our scheme. We also give an improved ID-DVPS.

Original languageEnglish
Pages (from-to)948-954
Number of pages7
JournalComputers and Electrical Engineering
Issue number5
Publication statusPublished - 2010 Sep


  • Cryptography
  • Identity-based signatures
  • Proxy signatures
  • Strong designated verifier signatures
  • Universal forgery attack

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Computer Science(all)
  • Electrical and Electronic Engineering

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