Cryptanalysis of an Identity Based Signcryption Scheme in the Standard Model

Yang Ming ； Yu-Min Wang

《International Journal of Network Security》 18卷1期 (2016/01) Pp. 165-171

https://doi.org/10.6633/IJNS.201601.18(1).18

並列摘要

Identity based signcryption (IBSC) is a novel cryptographic primitive that simultaneously provides the authentication and encryption in a single logic step. The IBSC has been shown to be useful in many applications, such as electronic commerce, mobile communications and smart cards. Recently, Li et al. (2013) [16] proposed a new identity based signcryption scheme and claimed that their scheme was provably secure in the standard model, i.e. (IND-IBSC-CCA2) semantically secure under adaptively chosen-ciphertext attack and (EUF-IBSC- CMA) existential unforgeable under adaptively chosen- message. However, in this paper, by giving concrete at- tacks, we show that Li et al's scheme is not secure in their security model. Additionally, we further indicate that Li et al's scheme also does not satisfy strongly existential unforgeability.

並列關鍵字

Existential unforgeability ； identity-based sign-cryption ； semantically security ； signcryption ； standard model