Skype users attacked by "Dorkbot"

Skype, the Internet communications service, is being targeted by hackers.

Cyber criminals have been using social engineering to spread a variant of "Dorkbot," a worm that infects Windows PCs.

Users of Skype have reported receiving an instant message reading, "lol is this your new profile pic?" which, when clicked, leads to an attached .zip file that proceeds to download the malware.

Following this, infected machines can be hijacked and recruited into a botnet army. Users can also be locked out of their computers and held to ransom; ordered to pay fees as high as $200 (£125) or face seeing their files permanently deleted.

Skype issued a statement on the matter, saying, "We are aware of this malicious activity and are working quickly to mitigate its impact. We strongly recommend upgrading to the newest Skype version and applying updated security features on your computer. Additionally, following links – even when from your contacts – that look strange or are unexpected is not advisable."

Avoiding the worm altogether is straightforward, but getting rid of it can be a completely different matter, though Skype has helpfully posted assistance and instructions for cleaning infected systems.

Infected computers, in turn, send out the "lol" message to their contacts.

For further information, visit the Skype forums.