Further improvement of Juang et al. s password-authenticated key agreement scheme using smart cards

Very recently, Sun et al. proposed an improved password authenticated key agreement scheme based on Juang et al. s scheme. However, after reviewing their scheme and analyzing its security, we find their scheme is vulnerable to two kinds of attacks, i.e., the offline password guessing attack, and the Denial-of-Service (DoS) attack. The analysis shows that Sun s scheme is insecure for practical application. Then, we propose a further improved scheme to eliminate the security vulnerability. Compared with Juang et al. s scheme and Sun et al. s scheme, our scheme is more secure and more suitable for real-life applications