CVE-2026-20500 Denial of service in MediaTek chipset

Medium 5.5 Published 7 Sep 2026 Updated 7 Sep 2026

A local attacker with user privileges can cause a system crash in MediaTek chipsets via improper input validation in the Modem component.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2026-20500?

CVE-2026-20500 is a medium-severity denial of service vulnerability in MediaTek, Inc. MediaTek chipset, published on 7 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In Modem, there is a possible system crash due to improper input validation. This could lead to local denial of service with User execution privileges needed. User interaction is needed for exploitation. Patch ID: MOLY01810811; Issue ID: MSV-9232.

Weakness: CWE-295

Which versions are affected by CVE-2026-20500?

It affects 22 products.

Products include Mediatek Mt2716 Firmware, Mediatek Mt6835 Firmware, Mediatek Mt6858 Firmware, Mediatek Mt6878 Firmware, Mediatek Mt6881 Firmware, Mediatek Mt6897 Firmware and 16 more.

How do I fix CVE-2026-20500?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-20500 being exploited?

There is no known exploitation of CVE-2026-20500 in the wild and no public exploit code.

Sources

Also known as A-528209857, ASB-A-528209857, GHSA-3wwc-gvmj-fpx5, M-MOLY01810811.