# CVE-2026-20589: MediaTek venc out-of-bounds write due to type confusion

Source: https://junglewise.ai/threats/cve-2026-20589-in-venc-there-is-a-possible-out-of-bounds-write-due-to-type  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-05. Updated: 2026-10-05  
License: CC BY 4.0 with a link back

CVE-2026-20589 · Severity: medium · CVSS 6.7 · Published 2026-10-05

MediaTek's venc (video encoder) component contains a memory corruption flaw that allows privilege escalation on devices using affected chipsets. An attacker who already has System-level privileges can exploit the type confusion vulnerability to write beyond allocated memory boundaries, potentially gaining full control of the device. No user interaction is required once System access is obtained.

Technologies: [MediaTek Dimensity 5G](https://junglewise.ai/threats/technologies/dimensity-5g), [MediaTek Genio IoT](https://junglewise.ai/threats/technologies/genio-iot), [MediaTek Helio 4G](https://junglewise.ai/threats/technologies/helio-4g), [MediaTek Kompanio](https://junglewise.ai/threats/technologies/kompanio). Vendors: [MediaTek](https://junglewise.ai/threats/vendors/mediatek).

## Quick answers

**Is CVE-2026-20589 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-20589 being exploited in the wild.

**How severe is CVE-2026-20589?** Medium severity, with a CVSS score of 6.7, published 5 October 2026.

**Which products and versions are affected?** MediaTek Dimensity 5G; MediaTek Helio 4G; MediaTek Genio IoT; MediaTek Kompanio.

**Is there a fix for CVE-2026-20589?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-20589 attacked?** It is attacked with local access, in device firmware.

**Am I affected by CVE-2026-20589?** Check whether you run MediaTek Dimensity 5G, MediaTek Genio IoT, MediaTek Helio 4G or one of the others listed. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The venc component suffers from an out-of-bounds write caused by type confusion, allowing an attacker with existing System privilege to corrupt adjacent memory. The vulnerability requires prior System-level access but no user interaction to exploit. A patch is available (Patch ID: ALPS11383899) to remediate this issue.

## Affected products

- MediaTek Dimensity 5G
- MediaTek Helio 4G
- MediaTek Genio IoT
- MediaTek Kompanio

## Timeline

- 2026-10-05: disclosed

## References

- [https://www.mediatek.com/product-security-bulletin/October-2026](https://www.mediatek.com/product-security-bulletin/October-2026)

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