Cryptanalysis of Wang et al's Certificateless Signature Scheme without Bilinear Pairings

In these years, the design of certificateless signature (CLS) scheme without bilinear pairings has been thoroughly investigated owing to its effectiveness on solving the key escrow problem in identity-based cryptography. In this paper, we identify that Wang et al.’s certificateless signature scheme cannot fulfil its security claims. We present a series of attack processes to demonstrate that Wang et al.’s scheme is insecure against a super