Cryptanalyses of A Two-factor User Authentication Scheme in Wireless Sensor Networks

Abstract

Wireless sensor network (WSN) is applied broadly to a range of significantly different networking environments. The open environment of WSN requires mechanisms which prevent unauthorized users from accessing resources. User authentication in WSN is a critical security issue. Recently, M.L. Das proposed a two-factor user authentication scheme in WSNs. However, Khan et al. showed that the M.L. Das's scheme does not provide mutual authentication between the gateway node and sensor nodes. And it is vulnerable to gateway node bypassing attack and privileged-insider attacks. A new user authentication scheme in WSN is proposed. Unfortunately, we find that Khan et al.'s scheme suffers from password guessing attacks and the stolen verifier attacks. Finally, we propose an improved scheme with better security strength and higher efficiency.