Cryptanalysis of a Certificateless Hybrid Signcryption Scheme and a Certificateless Encryption Scheme for Internet of Things

In wireless and mobile networks with limited storage and computing resources, certificateless cryptography has more advantages because of its low dependence on infrastructure and short security parameters. Recently, Gong et al. and Karati et al., respectively, proposed a new certificateless scheme in the Internet of Things environment, one of which is a certificateless hybrid signcryption scheme, and the other’s basis is a certificateless encryption scheme. Gong et al. and Karati et al. gave the formal security proof for their schemes, respectively. In this article, the attack algorithms against these two schemes are presented separately, thus proving that their schemes are insecure and not suitable for the Internet of Things environment.