# CVE-2026-20491: MediaTek med out-of-bounds write due to incorrect bounds check

Source: https://junglewise.ai/threats/cve-2026-20491-mediatek-med-out-of-bounds-write-due-to-incorrect-bounds-check  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-03. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-20491 · Severity: medium · CVSS 5.5 · Published 2026-08-03

MediaTek's med component, used in smartphone chipsets and IoT devices, contains a vulnerability that allows an attacker with local access and user-level privileges to trigger an out-of-bounds memory write. This could cause system crashes and service denial, or potentially allow unauthorized code execution, affecting the stability and security of connected devices.

Technologies: [MediaTek MT2735](https://junglewise.ai/threats/technologies/mt2735), [MediaTek Mt2735 Firmware](https://junglewise.ai/threats/technologies/mt2735-firmware), [MediaTek MT2737](https://junglewise.ai/threats/technologies/mt2737), [MediaTek Mt2737 Firmware](https://junglewise.ai/threats/technologies/mt2737-firmware), [MediaTek Mt6890](https://junglewise.ai/threats/technologies/mt6890), [MediaTek Mt6890 Firmware](https://junglewise.ai/threats/technologies/mt6890-firmware), [MediaTek MT6988](https://junglewise.ai/threats/technologies/mt6988), [MediaTek Mt6988 Firmware](https://junglewise.ai/threats/technologies/mt6988-firmware), [MediaTek MT6990](https://junglewise.ai/threats/technologies/mt6990), [MediaTek Mt6990 Firmware](https://junglewise.ai/threats/technologies/mt6990-firmware). Vendors: [MediaTek](https://junglewise.ai/threats/vendors/mediatek).

## Quick answers

**Is CVE-2026-20491 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-20491 being exploited in the wild.

**How severe is CVE-2026-20491?** Medium severity, with a CVSS score of 5.5, published 3 August 2026.

**Which products and versions are affected?** MediaTek med component.

**Is there a fix for CVE-2026-20491?** A patch was published on 2026-08-03: Patches ALPS10981478 and AUTO00851173 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-20491 attacked?** It is attacked with local access.

**Am I affected by CVE-2026-20491?** Check whether you run MediaTek Med Component, MediaTek MT2735, MediaTek Mt2735 Firmware 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 vulnerability is an out-of-bounds write in MediaTek's med component caused by an incorrect bounds check (CWE-787). Exploitation requires local access with user-level execution privileges; remote exploitation is not possible. The flaw affects multiple MediaTek chipsets including MT6890, MT6990, MT6988, MT2735, and MT2737. An attacker can trigger denial of service or potentially escalate privileges through memory corruption. MediaTek has issued patches with IDs ALPS10981478 and AUTO00851173 for affected chipsets.

## Affected products

- MediaTek med component

## Timeline

- 2026-08-03: disclosed
- 2026-08-03: patched: Patches ALPS10981478 and AUTO00851173 released

## References

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

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