Certificateless cryptography;‎ Aggregate signature scheme;‎ Forgeability;‎ Insecurity

Abstract
Recently, Nie et al.‎ proposed a certificateless aggregate signature scheme.‎ In the standard security model considered in certificateless cryptography, we are dealing with two types of adversaries.‎ In this paper, we show that Nie et al.‎'s scheme is insecure against the adversary of the first type.‎ In other words, although they claimed that their proposed scheme is existentially unforgeable against adaptive chosen message attack considering the adversaries in certificateless settings, we prove that such a forgery can be done.‎