Malware authors are using the popularity of the Angry Birds series of games as a way to infect the smartphones of users who download the exploit from unofficial Android app stores, according to a security software firm.
In an April 12 post on SophosLabs’ NakedSecurity blog, Graham Cluley said the Trojan horse masquerades itself as the Angry Birds Space game. When downloaded, the malware installs its malicious code onto the device.
“The Trojan horse, which Sophos detects as Andr/KongFu-L, appears to be a fully functional version of the popular smartphone game, but uses the GingerBreak exploit to gain root access to the device, and install malicious code,” Cluley wrote. “The Trojan communicates with a remote Website in an attempt to download and install further malware onto the compromised Android smartphone.”
Andr/KongFu-L is a known Android Trojan.
Once the malware is installed and the Android device compromised, cyber-criminals can then send instructions that will lead to more malicious code being downloaded or URLs to be displayed in the smartphone’s browser, he wrote.
“Effectively, your Android phone is now part of a botnet, under the control of malicious hackers,” Cluley wrote.
The Trojan that pretends to be the Angry Birds Space game from Rovio can be downloaded from third-party unofficial Android app stores, though SophosLabs did not name any of those stores. Cluley said the version of Angry Birds Space in the Google Play, Google’s official apps store—formerly called Android Market—is not affected by the malware.
Rovio also posted a warning on its Website about malware-infested versions of the game: “As you get ready to pop pigs in zero gravity, watch out for fake versions of Angry Birds Space, and make sure to download safe by getting the official game from Rovio.”
As smartphones increase in popularity with both enterprise users and consumers, they’re also becoming a growing target of cyber-criminals. According to a report released in February by Juniper Networks, malware specifically targeted at mobile operating systems more than doubled in 2011, growing by 155 percent across all platforms—including Apple’s iOS, Google’s Android, Research In Motion’s BlackBerry and Nokia’s Symbian.
Android saw the biggest leap in malware incidents, according to the Juniper report. Malware targeting Android grew 3,325 percent in the last seven months of 2011, and Android malware accounted for 46.7 percent of unique malware samples that targeted mobile platforms, followed by 41 percent for Java Mobile Edition.
According to Juniper, Android’s diverse and open marketplace—where developers can post their apps—and the platform’s growing market share made it an attractive target for cyber-criminals. It has almost half of the mobile operating system market, according to analysts.
"Hackers are incented to target Android, because there are simply more Android devices as compared to the competition," Daniel Hoffman, chief mobile security evangelist at Juniper, said when his company’s report was released.
Hoffman said Google's "Bouncer" service, which scans apps in the official Android market place and removes offenders, is making it more difficult for scammers to upload malicious apps. Bouncer, which began operating in the second half of the year, will "certainly help" reduce infection rates from downloads on the official market of known threats, he said.
Sophos’ Cluley said users of Android-based mobile devices need to take care when they decide to download an app.
“It feels like we have to keep reminding Android users to be on their guard against malware risks, and to be very careful—especially when downloading applications from unofficial Android markets,” he said.