Firefox users can get infected with the malware by either getting tricked into downloading it, or even passively, via a so-called “drive-by” download.
The security firm BitDefender identified the malware, which registers itself under a package of plugins called “Greasemonkey” on PCs. When installed, the malware lies dormant in the application’s add-ons folder under the file name “Trojan.PWS.ChromeInject.A.”
When activated, the malware uses Javascript to collect password information from several banks, including Barclays, Wachovia, Bank of America and PayPal. It then sends the information to a server in Russia.
Microsoft's Internet Explorer continues to command the vast majority of the market, 20 percent of all web surfers now turn to Firefox, according to market researchers at Net Applications, an online tracking firm.
That’s good news for Mozilla but bad news for Firefox surfers who haven’t had to contend with as many viruses and malware as Internet Explorer users.
BitDefender recommended that users only download signed, verified software to their systems. On a commercial basis, the company also offers an array of products to detect and fight viruses and malware.