The 'police virus' ransomware scam is still going strong despite a crime bust earlier this year saw the arrest of an East European gang accused of using it to attack large numbers of PC users, antivirus firm Panda Security has confirmed.
At the time Spanish police (working with Trend Micro) made the arrests public in February, it was assumed that the police virus' ransom campaign (also known as Reveton, the actual name of the malware) had been dealt a major blow.
This included the dismantling of the alleged financial wing of the campaign used to funnel proceeds from victims without attracting the attention of the authorities, comprising six Russians, two Georgians, two Ukrainians and the Russian mastermind picked up in secret while holidaying in Dubai in late 2012.
But new figures from security from PandaLabs for Q1 2013 show that the frequency of attacks on Windows users using this malware held steady in December, the month of the first Dubai arrest, rising to new highs in January and February.
To put this into context, PandaLabs was detecting 554 attacks in the first week of December 2012 among its user base, which had tripled by early February to 1,547 per week.
The firm's explanation is that Reveton is being used by a range of gangs as evidenced by a number of subtle variations in ransom attacks that still use the same 'police virus' scare tactic.
"For example, certain techniques which had supposedly been improved have reemerged (including encryption of files on compromised computers), or how different variants show the screen with the fake police warning using completely different functions, clearly illustrating that they are different projects," the company said.
PandaLabs doesn't state it explicitly but it could also be the case that the arrests simply cleared one competing gang from the scene, allowing the remaining ones to move on to their territory.
The company's figures don't extend beyond February but there is plenty of anecdotal evidence that the Reveton malware is still being developed.
According to a recent Microsoft analysis, the malware has been adjusted to steal passwords using a keylogging module that activates even if victims make the mistake of paying the ransom to have their PCs returned.