Computer security firms issued warnings on Friday over a computer virus that arrives by email offering downloads of "free sex movies" or documents.
McAfee Labs said the "Here you have" virus, which attacks users of computers running Microsoft's Windows operating system, takes its name from the subject line in the emails sent to unsuspecting recipients.
The emails provide a link to a website purporting to offer shared PDF documents or movie files but which actually execute the virus when clicked upon.
Once activated, the worm attempts to send the email on to all of the contacts in a recipient's address book, McAfee said.
In addition, it attempts to disable security programs hosted by a recipient's machine.
Kaspersky, another security firm, raised its threat level over the virus which it called "VBMania."
"The worm is pretty active, and currently sending out significant amounts of mail," it said.
According to Fox News, the virus took down servers at US space agency NASA and companies such as cable giant Comcast on Thursday.
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