The first mobile malware infection via drive-by-download has been detected.
The Android trojan was detected by Symantec researchers delivered through a fake security update hosted on malicious websites.
Drive-by-download transmitted malware to a victim's computer when victims visited infected web pages, but users still had to accept permission prior to installing.
“This is more of a social engineering attack,” Symantec Security Response Center operations director Liam O Murchu said. “At the end of the day, the user still needs to see a message and decide if it's something that they want to install or not.”
Infected devices may be used as a proxy to authorise attackers to route traffic, O Murchu said.
Trojans that have invaded mobile devices were typically used for financial gain or to access personal data, but the intent of the malware was unclear.
“Maybe they have a scheme in mind that they want to use these phones for at a later point,” he said.
Trail of Bits chief executive Dan Guido said the attack was "not surprising".
“In this case, they are just reusing someone else's website instead of running it off their own. If anything, this proves they are even lazier than ever before,” he said.
The number of victims was also unknown, but there were almost 1000 compromised sites pushing the trojan, according to O Murchu.
Android's mobile operating system was the platform of choice for criminal activity. This was aggravated by marketplaces outside of the official Android app store, Google Play, that allowed users to install applications which host malicious code.
“That was how a majority of the threats we saw last year were being distributed through Android,” O Murchu said.
Juniper's 2011 security report found that Android malware jumped 3325 percent compared to 2010.