Cryptanalysis of a Compact Anonymous HIBE with Constant Size Private Keys
Xi-Jun Lin, Lin Sun, Haipeng Qu, Hequn Xian · The Computer Journal · 2018
Abstract Recently, Zhang et al. proposed a new anonymous hierarchical identity-based encryption (anonymous HIBE) over prime order groups to achieve both constant size private key and constant size ciphertext. Moreover, a double exponent technique was used to provide anonymity. They proved that their scheme is secure and anonymous against chosen plaintext attacks in the standard model. In this paper, we point out that their scheme is insecure.