CVE-2016-10435

Vulnerability

A time-of-check time-of-use (TOCTOU) vulnerability exists in QTEE syscall handlers on Qualcomm Snapdragon Automobile, Mobile, and Wear platforms, including MDM9206, MDM9625, MDM9635M, MDM9640, MDM9645, MSM8909W, SD 210/SD 212/SD 205, SD 400, SD 410/12, SD 425, SD 430, SD 450, SD 615/16/SD 415, SD 617, SD 625, SD 650/52, SD 800, SD 808, SD 820, and SD 820A. The issue affects Android before the 2018-04-05 security patch level [1]. The TOCTOU flaw allows a race condition between a check and use of a resource within a syscall handler.

Exploitation

An attacker with local access or the ability to run malicious code on the device could exploit the race window in a QTEE syscall handler. Successful exploitation requires precise timing to manipulate the resource between the check and use [1].

Impact

If exploited, the attacker could achieve privilege escalation within the Qualcomm Trusted Execution Environment (QTEE), potentially gaining elevated privileges that could lead to further compromise of the device's security.

Mitigation

This vulnerability is fixed in the Android security patch level dated 2018-04-05 or later. Users should ensure their devices receive and apply this update. No workaround is available [1].