Android linux kernel privilege escalation (CVE-2014-4323)

In this blog post, we'll cover another Android linux kernel privilege escalation vulnerability I discovered, which could be used to achieve kernel code execution on Android devices.

This time we'll only go over the vulnerability, with no exploit, since I don't personally have any device which is vulnerable to this issue, and therefore couldn't write an exploit. However, we'll dream up an exploit together, which should be pretty simple to implement.

Before we start, I'd like to point out that this vulnerability has been responsibly disclosed to Qualcomm, and it has since been fixed (see "Timeline" below). It should be noted that this vulnerability was present in all Qualcomm-based devices based on the following chipsets:

• APQ 8064 (Snapdragon S4 Pro)
• MSM 8960 (Snapdragon S4)
• MSM 8660 (Snapdragon S3)
• MSM 8x30
• MSM 7x30

So all devices based on these SoCs (such as the Nexus 4, Nexus 7, etc.), with kernels dated before December 2014, should be vulnerable (see "Timeline" below).