SophosLabs has identified that malware designed to install the Dorkbot worm onto users computers is being spread via Facebook chat. For now at least Facebooks built-in security systems are not preventing it. The worm tricking users into believing that they are clicking on a link to an image. The link may appear on casual observation to point to Facebook.com, but in reality it goes to a third-party website. Although an unsuspecting user may believe that they were clicking”]
Source: https://grahamcluley.com/facebook-chat-worm-continues-spread/