Cryptanalysis of a biometric-based remote user authentication scheme

A three-factor (password, smart card and biometric) authentication scheme allows a user and a remote server to authenticate each other, and it provides strong authentication. Very recently, Das proposed a three-factor remote authentication scheme. He claimed that their scheme was more secure than Li-Hwang´s scheme. However, we demonstrate that his scheme is vulnerable to various attacks. It is not feasible for real-life implementation. We then suggest an improvement. The proposed scheme is proved to be more secure than the previous related works and maintains low computation and communication cost.