SMS-controlled Malware Hijacking Android Phones

Researchers at NQ Mobile, working alongside researchers at North Carolina State University, have discovered new Android malware that is controlled via SMS that can do a number of things on the compromised device including recording calls and surrounding noise.

Called TigerBot, the recently discovered malware was found circulating in the wild via non-official Android channels. Once again, this discovery is proving the sensibility of only installing official applications, and only those available from known, legitimate sources such as Google Play.

TigerBot will hide itself on a compromised device by forgoing an icon on the home screen, and by masking itself with a legit application name such as Flash or System. Once installed an active, it will register a receiver with a high priority to listen to the intent with action "android.provider.Telephony.SMS_RECEIVED."

"Upon receiving a new SMS message, TigerBot will check whether the message is a specific bot command. If so it will prevent this message from being seen by the users and then execute the command accordingly," NQ explained on their blog.

Based on the code examination, NQ said that TigerBot can record sounds in the immediate area of the device, as well as calls themselves. It also has the ability to alter network settings, report its current GPS coordinates, capture and upload images, kill other processes, and reboot the phone.

"Our analysis shows that some of the above commands may not be perfectly supported... [For example] the command to kill other processes may only work on early Android versions," NQ added.

The fact that TigerBot and any variants can be controlled without the user's knowledge marks it as a serious risk, the mobile security firm said.

Again, the best bet to avoid infection comes from sticking to legit sources when downloading applications.

In addition, NQ said that users should always reject application requests from unknown sources, closely monitor permissions requested by any application, and reminded that applications shouldn't request permission to do more than what it offers in its official list of features.