An untraceable temporal-credential-based two-factor authentication scheme using ECC for wireless sensor networks

Recently, He et al. proposed an anonymous two-factor authentication scheme following the concept of temporal-credential for wireless sensor networks (WSNs), which is claimed to be secure and capable of withstanding various attacks. However, we reveal that the authentication phase of their scheme has several pitfalls. Firstly, their scheme is susceptible to malicious user impersonation attack, in which a legal but malicious user can impersonate...