Attackers are using a Windows banking trojan to inject malicious content into Facebook, which they hope will ultimately lure unsuspecting users into downloading a nasty piece of malware on their Android devices, according to researchers with ESET.
The attack begins by infecting a user's computer with the Qadars banking trojan, which is usually done via drive-by download, Jean-Ian Boutin, an ESET malware researcher who posted about the attack on Wednesday, told SCMagazine.com on Friday.
“The Trojan is able to intercept a webpage downloaded from a webserver, inspect it and inject new content into the page before showing it to the user,” Boutin said. “In the webinject configuration file I received, one of the targets was the Facebook website.”
With that webinject file for the popular social media website unknowingly downloaded to the computer, the Qadars malware will inject content into Facebook that will not only allow it to steal credentials that are used, but it will also redirect users to a phony Facebook verification page, Boutin explained.
Here, if a user enters their phone number and indicates they have an Android device, an SMS with a link is sent to the device that, if clicked, will download Android malware known as iBanking, Boutin said, adding the user is instructed to scan a QR code or use the Android browser if the SMS is not received.
What happens next is that the user follows a step-by-step instruction process to install the iBanking malware, which all the while disguises itself as a legitimate Facebook app, Boutin said, explaining that when iBanking is installed, attackers are able to redirect incoming voice calls, or even capture audio.
But that may not be the worst part.
“Once the user phone is infected with iBanking, any SMS can be diverted,” Boutin said, explaining this feature is used by attackers to circumvent security features that utilize SMS messages. “Thus, websites using the user's mobile as a means to implement two-factor authentication could be abused.”
Attackers targeting Facebook to install iBanking on Android devices is a new tactic, Boutin said, explaining that attackers previously targeted online banking websites to deliver the malware. He said the shift to Facebook may have been due to its wider audience, and because it requires less customization in order to fool the user.