Hackers have subverted warnings generated by Firefox about dangerous sites to punt fake anti-virus portals.
Surfers straying onto a web page offering the "Security Tool" rogue anti-virus are offered a warning page that convincingly mimics the genuine Firefox block page. The site offers supposed updates for Mozilla's technology that are actually scareware packages.
If Windows users apply these updates they will be falsely warned that their system is infected and continuously nagged into buying worthless scareware packages that serve only to line the pockets of cyber-scammers.
The rogue application will automatically attempt to install itself on the machines of prospective marks in cases where scripts are enabled, net security firm F-Secure warns.
Firefox's genuine attack warning technology is all server-side and never requests that users download updates. The attack relies, in part, on the ignorance of the majority of potential victims on this point.
The attack is a rare but not unprecedented attempt by malware slingers to use Firefox features to push their wares. Previous attacks by the same gang have involved tricking users into downloading scareware in the guise of a supposed Firefox/Flash update.
The malware is offered from a page designed to trick Firefox users into thinking their browser software has just been updated but that they still need to apply a Flash Player patch, which is actually a rogue anti-virus installation utility. The sneaky tactic, first spotted back in July, is explained in more detail in a blog post by F-Secure here. ®