MediaTek MCU: MT2737/MT6880/MT6890/MT6990 SecureBoot Heap Overflow PrivEsc
CVE-2026-20466 Published on August 3, 2026

In sec boot, there is a possible escalation of privilege due to a heap buffer overflow. This could lead to local escalation of privilege, if an attacker has physical access to the device, with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: AUTO00845351 (Note: For MT2737) / ALPS11072643 (Note: For MT6880, MT6890, MT6990); Issue ID: MSV-6929.

NVD

Vulnerability Analysis

CVE-2026-20466 is exploitable with physical access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality and integrity, and no impact on availability.

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

Weakness Type

What is a Memory Corruption Vulnerability?

The software writes data past the end, or before the beginning, of the intended buffer. Typically, this can result in corruption of data, a crash, or code execution. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent write operation then produces undefined or unexpected results.

CVE-2026-20466 has been classified to as a Memory Corruption vulnerability or weakness.


Affected Versions

MediaTek, Inc. MediaTek chipset: