Security Weakness in the Smart Grid Key Distribution Scheme Proposed by Xia and Wang

In this paper, we show that the cryptographic key generation and distribution scheme for the smart gird proposed by Xia and Wang is vulnerable to the impersonation attack by which the adversary is able to impersonate the responder to the initiator. Furthermore, on the basis of this vulnerability, we point out that Xia and Wang's argument for resistance against the unknown key share (UKS) attack is incorrect.