Cryptanalysis of an Asymmetric Searchable Encryption Scheme

With the rapid growth of information and popularity of outsourced data, most of the IT companies are motivated to outsource their sensitive information on cloud servers. Since these servers are not fully trusted, for preserving privacy and security, these data must be encrypted before being outsourced. For searching on the encrypted data, searchable encryption method plays an important role. Recently, Tajiki et al. have proposed a new asymmetric searchable encryption called Secure Searchable Asymmetric Encryption (SSAE). They claimed their scheme is secure against forgery attack. In this paper, at first, we show that the security of SSAE is not complete by presenting a forgery attack on this scheme. After that we modify the SSAE to withstand this forgery attack.