A critical out of bounds write vulnerability in the MediaTek WLAN AP driver could allow a local attacker to escalate privileges on the affected system.

This vulnerability involves a stack-based buffer overflow (CWE-121) triggered by an incorrect bounds check within the WLAN AP driver. Successful exploitation requires the attacker to possess local user execution privileges, though no user interaction is required to trigger the flaw.

The vulnerability carries a CVSS score of 7.8, indicating a high severity risk. Successful exploitation allows a local user to achieve full privilege escalation, which could result in a total compromise of the affected device or system. Such access could lead to the unauthorized modification of system configurations, data exfiltration, or the disruption of critical network services.

Immediate Action: Update the affected MediaTek WLAN AP driver to the version specified in the November 2025 vendor security bulletin (Patch ID: WCNCR00435343).

Proactive Monitoring: Monitor system logs for unusual kernel-level activity or crashes related to the WLAN driver that may indicate exploitation attempts.

Compensating Controls: Restrict local shell access to untrusted users and ensure that only authorized personnel have the ability to execute code on devices running the affected driver.

Public Exploit Available: Unknown

Given the potential for complete system compromise via privilege escalation, immediate patching is required. Organizations should prioritize updating all devices utilizing the affected MediaTek SDK versions to the latest available release to eliminate this attack vector.