ID: IRCNE2014072244
Date: 2014-07-09
According to “ComputerWorld”, A vulnerability present in most Android devices allows apps to initiate unauthorized phone calls, disrupt ongoing calls and execute special codes that can trigger other rogue actions.
The flaw was found and reported to Google late last year by researchers from Berlin-based security consultancy firm Curesec, who believe it was first introduced in Android version 4.1.x, also known as Jelly Bean. The vulnerability appears to have been fixed in Android 4.4.4, released on June 19.
However, the latest version of Android is only available for a limited number of devices and currently accounts for a very small percentage of Android installations worldwide. Based on Google's statistics, almost 60 percent of Android devices that connected to Google Play at the beginning of June ran versions 4.1.x, 4.2.x and 4.3 of the mobile OS. Another 13 percent ran versions 4.4, 4.4.1, 4.4.2 or 4.4.3, which are also vulnerable. Version 4.4.4 had not been released at that time.
The issue allows applications without any permissions whatsoever to terminate outgoing calls or call any numbers, including premium-rate ones, without user interaction. This bypasses the Android security model, where apps without the CALL_PHONE permission should not, under normal circumstances, be able to initiate phone calls.
The flaw can also be exploited to execute USSD (Unstructured Supplementary Service Data), SS (Supplementary Service) or manufacturer-defined MMI (Man-Machine Interface) codes. These special codes are inputted through the dial pad, are enclosed between the * and # characters, and vary between different devices and carriers. They can be used to access various device functions or operator services.
The new vulnerability might be exploited by malware for some time to come, especially since the patching rate of Android devices is very slow and many devices never get updated to newer versions of the OS.
The attack is not exactly silent, as users can see that a call is in progress by looking at the phone, but there are ways to make detection harder.
A malicious app could wait until there is no activity on the phone before initiating a call or could execute the attack only during nighttime. The app could also completely overlay the call screen with something else, like a game.
