Smut page ransomware Trojan ransacks browsers

Russian cybercrooks have come up with a variant of ransomware scams, which works by displaying an invasive advert for online smut in users' browsers that victims are extorted to pay to remove.

The Ransompage Trojan will display a persistent ad inline on every page that a surfer on an infected Windows machine visits. The ad for a pornographic website covers parts of the original webpage, making it even more annoying. Accompanying Russian-language text instructs victims that in order to remove the ad - and gain access to an online smut site in the process - they need to send a premium rate text message.

"The premise is that the victim will become so frustrated or embarrassed by the ad that they will succumb to the pressure and send the SMS text message," security firm Symantec explains.

Symantec - which has a full write-up of the scam, including browser screen-shots - likens the attack to ransomware, types of malware that encrypt local files in an attempt to extort users into purchasing a decryption utility.

The Ransompage Trojan works with multiple browsers, including Internet Explorer, some versions of Firefox and Opera. However the malware is not compatible with the latest version of Firefox, giving an easy escape route.

The Trojan is either dropped onto already compromised systems by other strains of malware, or downloaded from malicious Web sites. A small number of instances of infections have been recorded, Symantec reports, adding that removing the malware is straightforward. ®