This vulnerability (CVE-2026-20465) involves a heap-based buffer overflow (CWE-122) in the wlan AP driver of MediaTek chipsets. The root cause is a missing bounds check that permits an out-of-bounds write. An attacker in proximity or adjacent network position can exploit this flaw to escalate privileges remotely without needing user interaction or additional execution privileges. The affected products are MediaTek chipsets MT6890, MT7915, MT7916, MT7981, and MT7986. The vulnerability was published on 2026-08-03 and has a CVSS v3.1 base score of 8.1 (AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N), reflecting high impact on confidentiality and integrity but no impact on availability. There is no vendor advisory or patch information available at this time.

Successful exploitation allows a remote attacker with adjacent network access to escalate privileges on the affected MediaTek chipset without requiring user interaction or additional execution privileges. The impact includes high confidentiality and integrity compromise but does not affect availability. This could enable unauthorized access or control over affected devices using these chipsets.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary mitigation has been published by MediaTek at this time. Users and administrators should monitor MediaTek's advisories for updates and apply patches promptly once available.