The security researcher who last year sucked thousands of IDs out of Apple's Developer Centre site has turned his gaze onto Android and turned up a bug that Trend Micro says is exploitable.
According to Ibrahim Balic, the bug causes memory corruption on Android 4.2.2 , 4.3 and 2.3 at least, but he suspects all Android versions may be affected.
That blog post, along with Balic's report that a malformed APK containing the bug crashed Google's Bouncer infrastructure, has now been confirmed in more – and better-written – detail by Trend Micro, here.
Trend writes: “We believe that this vulnerability may be used by cybercriminals to do some substantial damage on Android smartphones and tablets, which include “bricking” a device, or rendering it unusable in any way. In this context, the device is “bricked” as it is trapped in an endless reboot loop.”
Balic writes that if an attacker sets appname in strings.xml to a value greater than 387,000 characters, the bug is triggered. Trend Micro provides more detail, saying that the attack triggers memory corruption in Android's WindowManager (used to control the placement and appearance of windows).
An attacker needs only conceal a hidden Activity label in a package, Trend Micro says, to brick the target. If the attacker were to create malware that auto-started on power-up, the user's only option would be to completely wipe the device via a boot loader recovery.
Trend says the problem goes beyond Balic's post:
“PackageManager and ActivityManager are also susceptible to a similar crashing vulnerability. The critical difference here is that the user’s device will crash immediately once the malicious exploit app is installed. Note that the exploit app in this case does not need any special permission.”
Google has been notified of the issue. ®