MediaTek Power HAL OOB Write Escalates Privileges
CVE-2026-20509 Published on September 7, 2026

In Power HAL, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege if a malicious actor has already obtained the System privilege. User interaction is not needed for exploitation. Patch ID: ALPS11165543; Issue ID: MSV-9011.

NVD

Vulnerability Analysis

CVE-2026-20509 can be exploited with local system access, and requires user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.

Attack Vector:
LOCAL
Attack Complexity:
LOW
Privileges Required:
HIGH
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
HIGH
Integrity Impact:
HIGH
Availability Impact:
HIGH

Weakness Type

What is a Stack Overflow Vulnerability?

A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).

CVE-2026-20509 has been classified to as a Stack Overflow vulnerability or weakness.


Affected Versions

MediaTek, Inc. MediaTek chipset: