CVE-2026-20542 Use after free in MediaTek chipset

Medium 6.7 Published 5 Oct 2026 Updated 6 Oct 2026

A use-after-free vulnerability in MediaTek chipsets allows local privilege escalation for attackers with System privileges.

Exploited in the wild: Not known
Login needed: An administrator
Attackable: Local or same network only
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-20542?

CVE-2026-20542 is a medium-severity use after free vulnerability in MediaTek, Inc. MediaTek chipset, published on 5 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In apusys, there is a possible memory corruption due to use after free. 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: ALPS11076799; Issue ID: MSV-8143.

Weakness: CWE-416

Which versions are affected by CVE-2026-20542?

It affects 19 products.

Products include Mediatek Mt2718 Firmware, Mediatek Mt6878 Firmware, Mediatek Mt6897 Firmware, Mediatek Mt6899 Firmware, Mediatek Mt6989 Firmware, Mediatek Mt6991 Firmware and 13 more.

How do I fix CVE-2026-20542?

No fix has been published for CVE-2026-20542 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2026-20542 being exploited?

There is no known exploitation of CVE-2026-20542 in the wild and no public exploit code.

Sources

Also known as GHSA-2v6f-cp2c-9f7v.