Cryptanalysis of a secure and lightweight authentication protocol for wearable devices environment

Due to the rapid development in wireless communication technologies, wearable devices have become an indispensable part of this digital world. Recently, Das et al. have designed a secure and lightweight authentication protocol for wearable devices and claimed that it provides various security features like user anonymity, mobile terminal stolen attack, replay attack, etc. However, in this paper, we analyze the security of this scheme and find that it is not resistant to the mobile terminal stolen attack, denial of service attack and does not provide the secrecy of the session key.