Google, which has been criticised by Microsoft for recent bug disclosures, is now downplaying a bug of its own.
Core Security reckons there's a bug in the Android implementation of WiFi Direct, which if exploited would let an attacker force a reboot of a device. Google, however, isn't convinced it's critical, and isn't showing much interest in a patch.
According to Coresec's disclosure on Seclists, the bug is in the modified wpa_supplicant function that provides the interface between the wireless driver and the Android platform.
If the attacker sends a malformed wpa_supplicant event, the disclosure states, Android's WifiP2pDevice class throws an IllegalArgumentException, crashing the device: “a device name attribute with specific bytes generates a malformed supplicant event string that ends up throwing the IllegalArgumentException”, the disclosure states.
The vulnerability would occur while the Android device is scanning for other WiFi Direct-enabled devices (other phones, printers, cameras, and so on).
According to the timeline Core provides in its disclosure, Google classified the vulnerability as low severity, with the Android Security Team stating multiple times – the most recent on January 20 – that it has no timeline for a fix.
Threatpost quotes Duo Security's Jon Oberheide as broadly agreeing with Google, because the vuln only exists during a “limited vulnerability window” – the device has to be looking for peers, and the attacker has to be nearby so as to send the malformed data to the target, and its impact is limited to a reboot.
So far, Core has confirmed the bug on Nexus 4 and 5 devices running Android 4.4.4, LG D806 and Samsung SM-T310 devices on Android 4.2.2.