Robust Certificateless Signature Scheme without Bilinear Pairings

Abstract

During these years, the research field of certificateless signature (CLS) scheme without bilinear pairings is promptly investigated as the key escrow problem in identity-based cryptography can be solved via this concept. In this paper, we demonstrate that a certificateless signature scheme proposed by Gong and Li cannot fulfil its security claims. The authors argued that their proposed certificateless signature scheme is able to resist to the type of super adversary. However, this security argument can be improved. We present a series of attack processes to point out that Gong and Li's scheme is insecure against a super type I ad-versary. A remedy mechanism is then proposed to provide the security enhancement .