U.S. Power grid system is based on control system software from Siemens AG. This system has been targeted by Stuxnet malware recently.
According to Computerworld, Stuxnet exploits a Windows flaw to find and steal industrial data from supervisory control and data acquisition (SCADA) systems running Siemens’ Simatic WinCC or PCS 7 software.
SCADA systems are used to control critical equipment at power companies, manufacturing facilities, water treatment plants and nuclear power operations. This malware is the first publicly known malicious software program written specifically to exploit vulnerabilities in a SCADA system.
Furthermore, it was a report in The Wall Street Journal about the cyber-spies from China, Russia and elsewhere who had gained access to the U.S. electrical grid and installed malware tools that could be used to shut down service recently. However, a group of cybersecurity specialist has been deployed from U.S. department of homeland security to study and investigate the U.S. department of energy network after this report.