Security firms are warning about a rash of police-themed ransomware attacks.
The Reveton Trojan warns victims that illegal content has supposedly been detected on infected machines, displaying a message supposedly from local police agencies demanding payment to unlock machines.
To unlock an infected machine, marks are invited to purchase a Paysafecard and pay €100 to obtain an unlock code. But in reality users need not hand over any dosh to regain control of their PCs. Control of infected machines can be established by following a few simple steps, as outlined in a blog post by F-Secure here. Similar recovery instructions from Microsoft can be found here.
Cybercrooks are obviously hoping that victims will be panicked into complying with their demands without seeking external help.
"Even when somebody is savvy enough to recognise the message is a fake, the malware's accusations of offensive materials having been discovered on the user's hard drive creates a chilling effect, which has likely prevented some folks from seeking outside help," the Finnish security firm notes.
Trend Micro reckons some of the people peddling the Reveton Trojan were also involved in the high-profile DNSChanger Trojan scam, the target of a successful Microsoft takedown operation last November.
"The same people peddling this Trojan are also heavily involved in other malware and are very invested in this business," writes David Sancho, a senior threat researcher at Trend Micro. "For instance, we have found that they were affiliates of the DNSChanger Trojan program called Nelicash that Rove Digital was sponsoring for a few years.
"The main persons behind Rove Digital were arrested on November 8 2011 after a two year investigation by the FBI, the NASA Office of the Inspector General and Estonian police in collaboration with Trend Micro and other industry partners. So we might have found an important clue who is behind the police Trojan." ®