CVE record · CVE-2026-20509

Stack-based buffer overflow in MediaTek, Inc. MediaTek chipset

CVSS 6.7 MediumEPSS 0.0017 · 6th percentile

Published by the CVE Program (CNA: MediaTek) at 7 Sept 2026, 01:57 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
MediaTek, Inc.	MediaTek chipset	affected MT2718 affected MT6739 affected MT6761 affected MT6765 affected MT6768 affected MT6769 affected MT6781 affected MT6789 affected MT6833 affected MT6835 affected MT6853 affected MT6855 and 28 more Other versions: unaffected

Identifiers: CVE-2026-20509
CNA: MediaTek
Weakness (CWE): CWE-121
Tags: MediaTek, Inc. MediaTek chipset
Memory corruption
Published: 7 Sept 2026
Updated: 8 Sept 2026

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
6.7	Medium	3.1	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H	ADP (CISA-ADP)

CISA KEV Not listed.
EPSS 0.0017, the 6th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

This record came from the full history of the CVE Program, published 7 Sept 2026. New records show when each source confirmed them.

Sources

References from the CNA

www.mediatek.com/product-security-bulletin/September-2026

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.