CVE-2026-20513 Overview
CVE-2026-20513 is an information disclosure vulnerability in the MediaTek Audio Hardware Abstraction Layer (HAL). The flaw stems from improper input validation [CWE-35] in the Audio HAL component. A local attacker who has already obtained System privilege can exploit the issue to disclose sensitive information without user interaction. MediaTek tracks the fix under Patch ID ALPS11087533 and Issue ID MSV-8245, released in the MediaTek Security Bulletin for September 2026.
Critical Impact
Successful exploitation enables local information disclosure on affected MediaTek-based devices when the attacker already holds System-level privileges.
Affected Products
- MediaTek chipsets referenced in the September 2026 Security Bulletin
- Android devices integrating the vulnerable Audio HAL component
- Devices running firmware prior to Patch ID ALPS11087533
Discovery Timeline
- 2026-09-07 - CVE-2026-20513 published to the National Vulnerability Database
- 2026-09-08 - Last updated in the NVD database
- September 2026 - MediaTek publishes fix in the MediaTek Security Bulletin September 2026
Technical Details for CVE-2026-20513
Vulnerability Analysis
The vulnerability resides in the Audio HAL, the abstraction layer that bridges the Android audio framework with vendor-specific audio hardware drivers. Improper input validation in a path-handling routine allows an attacker to influence how inputs are processed by the HAL. The condition is classified as CWE-35 (Path Traversal: .../...//), indicating that traversal sequences are not correctly neutralized. Because the Audio HAL runs with elevated privileges within the device's media stack, mishandled input can expose memory contents or file data that should remain isolated from the caller.
Exploitation requires the attacker to already hold the System privilege, which constrains the practical impact. The vulnerability does not enable code execution or data modification, and it does not affect availability. It provides a mechanism for a compromised System-level process to escalate its access to sensitive information beyond what its role should permit.
Root Cause
The root cause is missing or insufficient validation of input passed into the Audio HAL. Untrusted values reach a code path that interprets them without adequate sanitization, allowing controlled reads or path resolution outside intended boundaries. MediaTek addresses the defect with Patch ID ALPS11087533, tracked internally as MSV-8245.
Attack Vector
The attack is local. An adversary must first compromise a process running with System privileges on the target device. From that context, the attacker issues crafted requests to the Audio HAL to trigger the flawed validation path and read information they should not otherwise access. User interaction is not required.
No public proof-of-concept or exploit code has been released. Refer to the MediaTek Security Bulletin September 2026 for vendor technical details.
Detection Methods for CVE-2026-20513
Indicators of Compromise
- Unexpected access patterns from processes interacting with Audio HAL interfaces on MediaTek devices
- Presence of System-privileged processes making anomalous audio subsystem calls
- Device firmware or build fingerprints predating Patch ID ALPS11087533
Detection Strategies
- Inventory MediaTek-based devices and cross-reference build numbers against the September 2026 security patch level
- Review mobile device management (MDM) telemetry for devices missing the current Android security patch level
- Monitor for privilege escalation activity that could grant an attacker the System context required for exploitation
Monitoring Recommendations
- Track compliance with monthly Android security patch levels across the mobile fleet
- Alert on devices whose OEM update cadence lags the MediaTek September 2026 bulletin
- Correlate mobile threat defense signals for suspicious HAL or media server activity
How to Mitigate CVE-2026-20513
Immediate Actions Required
- Apply the vendor update containing MediaTek Patch ID ALPS11087533 as soon as it is delivered by the device OEM
- Enforce monthly Android security patch level compliance through MDM policy
- Restrict installation of untrusted applications that could serve as a foothold to obtain System privilege
Patch Information
MediaTek released the fix under Patch ID ALPS11087533 (Issue ID MSV-8245) in the MediaTek Security Bulletin September 2026. Device OEMs must integrate the patch into their firmware releases. Confirm remediation by validating that affected devices report an Android security patch level of September 2026 or later.
Workarounds
- No vendor-supplied workaround exists; patching is the only supported remediation
- Reduce the attack surface by limiting sideloaded applications and enforcing strong app vetting
- Retire or isolate devices that will not receive the September 2026 vendor update
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.