Doctor Web, the Russian information security software developer, warns users that Trojan.Winlock virus epidemic is gathering pace. The company reports the number of the Russian Federation citizens who have suffered from the virus came to several million people in January 2010 alone. The malignant program demands that a user send a paid text message to a certain number in order to have his or her Windows operation system unlocked. Doctor Web believes the damage comes to hundreds of millions of rubles.

Trojan.Winlock’s latest versions that first emerged in November 2009 are becoming increasingly dangerous. The virus developers are now asking for more and more money for unlocking the system, while the message window keeps popping up whatever the user is doing and thus makes working on a computer nearly impossible. What is more, the virus does not get deleted from the system automatically after a while; instead, it acquires additional functions. For instance, it can prevent the launch of certain programs such as file managers or information utilities within the infected system, thus making it harder to treat the problem, Doctor Web says.

‘We feel the authorities should pay attention to the problem. Their efforts in finding the people who register the numbers to which the paid text messages must be sent could help to reduce the number of victims. Also, we believe the mobile operators should make these numbers invalid as soon as a customer complains about them,’ the company declares.