The FBI isn't emailing you - but virus writers are

The FBI is warning the public about new malicious emails designed to appear as if they were generated by the law enforcement agency.

In a statement, the FBI detailed the threat, which attempts to lure email users into opening an attachment containing a computer virus.

The mail is disguised as correspondence warning people that their internet use has been monitored by the FBI's Internet Fraud Complaint Center and that they have "accessed illegal websites." The emails then direct recipients to open the virus-laden attachment to answer a series of questions.

The FBI said it is currently investigating the origin of the malicious email and indicated that it would never send unsolicited messages to the public. The agency further warned people against opening any email attachment sent to them from an unknown sender.

Spoofing, or the practice of sending unsolicited email meant to appear as if it were generated by a reliable or known source, is a problem that continues to plague everyone from the world's largest financial services companies to government agencies and individual email users. The issue has gained renewed attention as the number of spoofing campaigns linked to identity theft scams - also known as phishing attacks - has increased significantly during the last several years.

Security concerns recently have swirled around the integrity of the FBI's IT systems. In a recent audit of the agency's computing infrastructure, Justice Department officials said that the agency has failed to adequately address problems identified after the 11 September attacks. Much of the criticism centred on the FBI's inability to install its Virtual Case File system, software meant to improve the manner in which FBI workers share information.

In recent testimony before the Senate Select Committee on Intelligence, FBI Director Robert Mueller said that other nations, as well as terrorists, are focusing attacks on US information systems.

Matt Hines writes for CNET News.com