The infamous Stuxnet worm is capable of targeting U.S. infrastructure, although it has yet to adversely affect any domestic systems, a senior Department of Homeland Security official said earlier this week.

"That virus focused on specific software implementations, and those software implementations did exist in some U.S. infrastructure," Greg Schaffer, the department's assistant secretary for cybersecurity and communications, told reporters during a breakfast on Tuesday morning. "So, there was the potential for some U.S. infrastructure to be impacted at some level."

Stuxnet is a virus that was specifically designed to attack supervisory control and data acquisition systems manufactured by German industrial giant Siemens (News - Alert). These systems are often utilized to manage water supplies, power plants and other industrial facilities, making the worm especially dangerous for governments.

Experts in the cyber security field have speculated that Stuxnet may have been created by a government or a well-financed group of investors, as the worm is too complex to have been developed by a single hacker. The fact that the virus has done much of its damage in Iran has caused many experts to question whether Stuxnet was designed to sabotage the country's nuclear facilities, according to the AFP.

"It was a very tiered, very complex, very sophisticated virus," Schaffer told the Defense Writers Group.

He concluded the talk by noting that today's cyber attacks are much more dangerous than the "malicious defacements of Web pages" that the DHS dealt with in the past.

These highly-targeted attacks, which are becoming increasingly difficult to defend and mitigate, are now capable of damaging systems with immense value, he added.

Meanwhile, Schaffer deflected all questions related to WikiLeaks' disclosure of confidential U.S. diplomatic documents, noting that the Department of Homeland Security has its hands full protecting the nation's networks from malicious viruses like Stuxnet.

For more information on how Stuxnet poses a threat to domestic network security, check out this recent interview with Andy Hayter, anti-malcode manager at ICSA Labs.

Beecher Tuttle is a TMCnet contributor. He has extensive experience writing and editing for print publications and online news websites. He has specialized in a variety of industries, including health care technology, politics and education. To read more of his articles, please visit his columnist page.

Edited by Tammy Wolf