Forgery attacks on Kang et al.’s identity-based strong designated verifier signature scheme and its improvement with security proof
✍ Scribed by Ji-Seon Lee; Jik Hyun Chang; Dong Hoon Lee
- Publisher
- Elsevier Science
- Year
- 2010
- Tongue
- English
- Weight
- 199 KB
- Volume
- 36
- Category
- Article
- ISSN
- 0045-7906
No coin nor oath required. For personal study only.
✦ Synopsis
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.