The U.S. Federal Bureau of Investigation today warned computer users not to open a widely circulating e-mail that falsely claims to have been sent by U.S. authorities. The e-mail attempts to trick users into installing a variant of the Sober worm by telling them that they have been spotted on “illegal Web sites,” and asking them to click on an attached “list of questions.”
That ‘list’ of questions is attached as a .zip file and in fact contains the virus. Should the recipient open the attachment, it copies the worm to the hard drive, which then scours the system for email addresses to which it can send itself on to.
“These e-mails did not come from the FBI,” the FBI announced in a posted statement. “Recipients of this or similar solicitations should know that the FBI does not engage in the practice of sending unsolicited e-mails to the public in this manner.”
Variations of the Sober worm have been circulating for about two years now, and their code is sufficiently similar that they are all thought to have been written by one person, or perhaps by a small group of people, Cluley said.
By mentioning U.S. law enforcement, the worm writers have made it more likely that users will inadvertently launch malicious code, but they may also be goading the FBI and the CIA, Cluley said. “It seems a bizarre thing for the virus writer to do, to pick a fight with the FBI and CIA in this way.”
The FBI is taking the matter “seriously,” and is investigating, the agency’s statement said.
