Two Attacks on the Wu-Hsu User Identification Scheme

In 2000, Lee and Chang proposed a user identification scheme with key distribution preserving anonymity for distributed computer networks. Recently, Wu and Hsu pointed out that there are two weaknesses in the Lee-Chang scheme. They further not only proposed a new scheme to remedy the security leaks of the Lee-Chang scheme, but also reduced computation complexities and communication cost as compared with the Lee-Chang scheme. However, in this article we show that there are two attacks in their scheme.