Mobile Trojans Can Give Attackers An Inside Look

A number of research efforts may give companies another reason to focus on the security of their employees' mobile devices. Computer scientists and security researchers have increasingly looked at the capabilities of mobile phones -- not as repositories of sensitive data, but as conscripted insiders.

Take the recent PlaceRaider proof-of-concept Trojan. Researchers at the University of Indiana at Bloomington and the Crane Division of the Naval Surface Warfare Center (NSWC) created the program to take opportunistic pictures of offices and other spaces where a worker might use a smartphone. By secretly snapping pictures, identifying the best photos, and sending them back to home base, the Trojan can help an attacker construct a 3-D model of the environment and gain reconnaissance on a victim's work space.

"From the attackers' perspective, they can significantly increase their capabilities by using [smartphones as a sensor platform]," said Apu Kapadia, an assistant professor in informatics and computing at the university, and one of the paper's authors. "Not only do they have access to your digital data on your device, they can listen to your environment, they can look at your environment, and they can feel the environment through the accelerometer."

Other research efforts have also looked at mobile devices as potential spies into the workplace. A year ago, researchers from the Georgia Institute of Technology showed how an attacker could record information typed into a keyboard using the accelerometer of a phone laying nearby on a desk. And Kapadia and other researchers had previously looked (PDF) into using voice recognition to recognize important information during phone calls, such as credit-card account numbers.

The research highlights that mobile devices -- which usually include multiple cameras and microphones, an accelerometer, and GPS -- are capable sensor platforms from which attackers could potentially monitor a company from the inside. Businesses usually have no idea what devices employees have carried into a building and behind the firewall -- a problem that businesses need to remedy, says Cleve Adams, CEO of AirPatrol.

"They could come in and procure your IP without you knowing," Adams says. "If I had access to the company's building, and if I decide to capture that data, I could send it to whoever I wanted without anyone knowing it. How disastrous that would be for a business."

[ The mobile device explosion within the enterprise has opened up countless new technology opportunities, but one that is just now starting to be explored is the idea of turning a mobile device into the ultimate biometric hardware. See You're Nobody Without Your Mobile Device. ]

While there are no in-the-wild samples that suggest malware writers have matched researchers' visions, many applications on the Android operating system have broad permissions that allow them to do some of the basics, such as make phone calls, turn on the microphone, and send SMS messages, says Dan Hoffman, chief mobile security evangelist at Juniper Networks.

In a yet-to-be-published study of 1.7 million applications, Juniper has seen that many applications have basic spyware features, even when it's not warranted by the program's functionality. When a program for displaying comics has the capability to use the phone in the background, that's odd, Hoffman says.

"That's something that could be malicious in nature, or it could be something that shouldn't be in an application and is kind of overreaching," he says.

Defending against espionage attacks will be difficult because many of the features that can be turned against a company are exactly the features that make smartphones so useful. Employees will resist any call to leave their smartphones at home or curtail their use, and such measures would likely also hurt productivity.

Some changes to the way that smartphones operate could help. Requiring special permissions to access the accelerometer, forcing the camera to make a shutter sound, or require an actual screen touch to take a picture could make smartphones a bit less susceptible to secretive remote control. And a purely physical solution, such as a case that hides the camera or muffles the microphone until needed, could help.

Such measures, however, are still not seen as necessary -- yet, UI's Kapadia says.

"I became paranoid enough to start searching for cases that cover the camera lens," he says. "I wasn't persistent enough to find one, but I think they'll become more popular soon."

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