SECURITY PROPERTY OF CERTIFICATELESS SIGNATURE SCHEMES

In this study, we revisit the security models divided by the potential adversaries according to their attack power of certificateless signatures. Since certificateless signature(CLS) scheme’s introduction in 2003, there have been quite a number of CLS schemes proposed [1–9,11,12]. However, only few schemes are known to be secure against these adversaries. Some schemes are insecure against a type I adversary who can replace a user’s public key and against a type II adversary who can access to the master secret key of the system, separately. In this talk, we classify attacks according to their attack power of certificateless signatures and consider the certificateless cryptosystems used for designing certificateless signatures with additional functionality.