Facebook users are once again at the centre of a security scare as a new variant of the “Koobface” worm has emerged to target users of the social networking site.

The virus, which first emerged in July of this year, has returned to target the vulnerable Windows PC’s of Facebook users by duping potential victims into downloading malicious software.

The virus messages the Facebook friends of infected users and attempt to direct them to websites that purport to show video clips of animations. Users are then told that they are required to download the latest version of Adobe Flash to view the content and are prompted to download a file, which is actually the virus itself.

Once the virus is executed on a new PC, the process is repeated.

The video clips referred to in the new breed of the virus appear to be less sexually orientated that in previous versions, instead claiming to be videos of drunken behaviour or pranks.

Facebook have warned users about the threat, which comes just over a month after an Australian user revealed that 419 scammers were using the popular site to dupe users into parting with several thousand dollars.

The company has advised all users who believe that they may have been affected to reset their passwords, update their antivirus software and run a system scan to highlight and remove the worm.

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