Cryptanalysis of Kim Jiye et al.'s Two-Factor Mutual Authentication with Key Agreement in WSNs

—User authentication and key management play an important role in the security of WSNs (Wireless Sensor Networks). In WSNs, for some applications, the user needs to obtain real-time data directly from dedicated sensors. For this case, several user authentication schemes have been proposed in recent years. Among these schemes, Kim Jiye et. al’s scheme is very novel. However, in the current work, we find that Kim Jiye et. al’s scheme is still vulnerable to some attacks such as offline password guessing attack, user impersonation attack using his/her own smart card, sensor node impersonation attack and gateway node bypassing attack. In this paper, we give detailed cryptanalysis of Kim Jiye et. al’s two-factor mutual authentication with key agreement in WSNs.