Looks like CNET has a story of the FBI, and US Marshals Service being hit with an unknown virus. Below is their story.

The FBI and the U.S. Marshals Service were forced to shut down parts of their computer networks after a mystery virus struck the law-enforcement agencies Thursday, according to an Associated Press report.

A spokesperson for the U.S. Marshals Service confirmed that it had disconnected from Justice Department computers as a precaution after being hit with the virus, while an FBI spokesperson would only say that it was experiencing similar issues, according to the report.

“We too are evaluating a network issue on our external, unclassified network that’s affecting several government agencies,” FBI spokesman Mike Kortan told the AP.

The virus’ type and origin are unknown, but spokespeople for both agencies said agencies’ access to the Internet and e-mail was shut down while the issue was evaluated.

Government regulations require agencies to report any security issues to US-Computer Emergency Readiness Team (US-CERT), but a call to CERT late Thursday for comment was not immediately returned.

Like I have said, it only takes one outward facing machine to get in. I am sure their are tons of viruses and botnets out there going undetected. You just have to play the waiting game, update them, and make the traffic blend in…

(Via CNET)