CVE-2026-20492 Overview
CVE-2026-20492 is a race condition vulnerability in the MediaTek Audio Hardware Abstraction Layer (HAL). The flaw allows a local attacker with User execution privileges to render the system unresponsive without any user interaction. The issue is tracked as MSV-7583 and addressed through patch IDs ALPS10960026 (covering MT6880, MT6890, MT6990, and MT6988) and AUTO00851250 (covering MT2735 and MT2737). MediaTek disclosed the flaw in its MediaTek Security Bulletin for August 2026. The weakness is classified under [CWE-367] (Time-of-Check Time-of-Use).
Critical Impact
Successful exploitation results in local denial of service, causing the affected device to become unresponsive and impacting availability of the audio subsystem and dependent processes.
Affected Products
- MediaTek chipsets MT6880, MT6890, MT6990, MT6988 (mobile SoCs)
- MediaTek chipsets MT2735, MT2737 (automotive SoCs)
- Devices running the affected MediaTek Audio HAL implementation
Discovery Timeline
- 2026-08-03 - CVE-2026-20492 published to NVD
- 2026-08-03 - Last updated in NVD database
Technical Details for CVE-2026-20492
Vulnerability Analysis
The vulnerability resides in the MediaTek Audio HAL, the userspace abstraction layer that mediates between the Android audio framework and audio hardware. A race condition in this component allows concurrent execution paths to interfere with shared state. When the race is won by an attacker-controlled thread, the audio subsystem enters an inconsistent state that causes the system to hang.
Exploitation requires only local access with unprivileged User-level execution rights. No user interaction is required, which lowers the practical barrier for triggering the flaw from any installed application that can reach the Audio HAL interfaces.
Root Cause
The defect maps to [CWE-367] Time-of-Check Time-of-Use (TOCTOU). Between the validation of a resource state and its subsequent use, another thread can modify that state. The Audio HAL does not enforce sufficient synchronization primitives to ensure atomicity across the check-then-use sequence, resulting in inconsistent state handling that stalls the audio pipeline and blocks dependent system services.
Attack Vector
The attack vector is local. A malicious application running with standard User privileges can repeatedly invoke Audio HAL entry points from multiple threads to induce the race. Because integrity and confidentiality are not affected, the exploitation goal is limited to availability disruption. Refer to the MediaTek Security Bulletin for vendor technical detail.
Detection Methods for CVE-2026-20492
Indicators of Compromise
- Repeated device-wide unresponsiveness or audio service hangs shortly after launching or interacting with a specific third-party application.
- Kernel or audioserver logs showing repeated Audio HAL invocations from a single non-system UID prior to system stalls.
- Watchdog-triggered reboots correlated with heavy concurrent access to audio device nodes.
Detection Strategies
- Monitor mobile telemetry for anomalous crash and ANR (Application Not Responding) patterns tied to audioserver or Audio HAL processes.
- Inspect installed applications for unusual multi-threaded invocation of audio APIs that do not align with the app's stated function.
- Correlate device unresponsiveness events with recent app installations using endpoint or mobile threat defense telemetry.
Monitoring Recommendations
- Ingest Android system logs (logcat, dmesg) into a centralized log platform and alert on repeated Audio HAL faults.
- Track patch-level compliance on managed devices to confirm remediation of ALPS10960026 and AUTO00851250.
- For automotive deployments using MT2735 or MT2737, monitor infotainment head unit availability metrics for repeated resets.
How to Mitigate CVE-2026-20492
Immediate Actions Required
- Apply the MediaTek firmware updates containing patch IDs ALPS10960026 and AUTO00851250 as delivered by the device or vehicle OEM.
- Inventory devices using the affected MT6880, MT6890, MT6990, MT6988, MT2735, and MT2737 chipsets and prioritize them for update.
- Restrict installation of untrusted third-party applications on affected devices until patches are deployed.
Patch Information
MediaTek released fixes as part of the August 2026 security bulletin. Patch ID ALPS10960026 applies to MT6880, MT6890, MT6990, and MT6988. Patch ID AUTO00851250 applies to MT2735 and MT2737. Issue ID is MSV-7583. See the MediaTek Security Bulletin for the complete advisory and OEM coordination guidance.
Workarounds
- No official workaround exists; vendor patching is the required remediation path.
- Reduce risk by enforcing application allow-listing through mobile device management (MDM) until patches are applied.
- On automotive systems, limit sideloading and third-party application execution in the in-vehicle infotainment environment.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
