---

Abstract: Cyber-physical security of smart grid under attacks is a serious issue today. The technique of state estimation has been employed in such a large-scale system to ensure the reliability. Successful attacks on tampering these readings were shown for linear state estimation. For the more realistic nonlinear state estimation are used in real systems, the attack that requires the knowledge of system states (which are difficult to obtain, even for insiders) was proposed. Up to our best knowledge, there are no research results that are able to give an attack to any buses without the knowledge of system states. This research paper provides such an attack. Demonstrations on IEEE test system show that the smart grid can be exploited by launching such attacks even without system state information. The strategy to generate such an attack is simple and easy to implement. Thus, the results in this paper show that a more realistic threat to the smart grid system. Hopefully the community could revisit the tampered reading detection algorithms to come up with a more sophisticated solution to avoid this vulnerability.

---