Google this week released a new set of Android security patches, meant to resolve numerous Critical bugs in the mobile platform, including the recently revealed QuadRooter flaws.
Unlike previous monthly security updates, the September 2016 Android Security Bulletin was split into three patch levels: the 2016-09-01 security patch level, addressing various platform-wide issues, the 2016-09-05 security patch level, meant to resolve bugs in drivers, OEM-related software, and various kernel subsystems, and 2016-09-06 security patch level, which fixes two QuadRooter vulnerabilities.
Overall, this month’s security patches resolve 55 vulnerabilities in Android: 8 were rated Critical, 30 are High risk, and 17 Moderate. Most of the bugs could result in elevation of privilege on the affected devices, but remote code execution flaws, along with information disclosure and denial of service issues were also addressed. Just as before, some of these flaws affect Android’s Mediaserver component.
The 2016-09-01 security patch level resolves two Critical remote code execution flaws (RCE) in LibUtils and Mediaserver (CVE-2016-3861 and CVE-2016-3862), and a High risk RCE in MediaMuxer. It also patches three elevation of privilege (EoP) and five denial of service (DoS) issues in Mediaserver, along with two EoP bugs in device boot and Settings, all rated High risk.
Of the Moderate vulnerabilities it resolves, 8 are EoP issues (affecting Telephony, Notification Manager Service, Debuggerd, System UI Tuner, Settings, SMS, and Java Debug Wire Protocol), 3 are information disclosure bugs affecting (Mediaserver, AOSP Mail, and Wi-Fi), and one is a DoS flaw in Telephony. Some of these issues don’t affect Nexus devices on Android 7.0 with all available updates installed, Google says in its security advisory.
The 2016-09-05 security patch level addresses multiple EoP vulnerabilities as well, including 5 rated Critical (in kernel’s security subsystem, networking subsystem, netfilter subsystem, and USB driver) and 14 rated High risk (affecting kernel’s sound subsystem, ASN.1 decoder, networking driver, and eCryptfs filesystem; Qualcomm subsystem, camera, sound, IPA, power, and Wi-Fi drivers, Qualcomm radio interface layers; Synaptics touchscreen driver; Broadcom Wi-Fi driver, and NVIDIA kernel.
Other High risk bugs resolved by this patch level include three DoS bugs in kernel networking subsystem and kernel ext4 file system, along with “Vulnerabilities in Qualcomm components.” The security update also fixes 4 Moderate risk information disclosure bugs in Qualcomm SPMI driver, Qualcomm sound codec, Qualcomm DMA component, and kernel networking subsystem, along with one DoS vulnerability in kernel networking subsystem, also rated Moderate.
The third part of the new Security Bulletin, the 2016-09-06 security patch level, is responsible for patching the aforementioned QuadRooter bugs. Revealed in early August, these issues (four in total) were said to affect over 900 million Android devices that use Qualcomm chipsets. Google’s new security patches resolve 2 of these bugs, namely CVE-2016-5340, a Critical EoP in kernel shared memory subsystem, and CVE-2016-2059, a High risk EoP in Qualcomm networking component.
According to Google, it decided to split this month’s security bulletin into three to provide device manufacturers with increased flexibility: “This bulletin has three security patch level strings so that Android partners have the flexibility to fix a subset of vulnerabilities that are similar across all Android devices more quickly. Android partners are encouraged to fix all issues in this bulletin and use the latest security patch level string.”
In July, Google decided to split its monthly security updates in two different patch levels, one of which focused on resolving bugs in OEM software. The company made this move after multiple Qualcomm components were found to pack critical vulnerabilities that impact the vast majority of Android devices out there. Last month, the company patched 81 vulnerabilities in drivers and components, most of which were reported in 2014.