CVE-2025-20709: mt6890 Buffer Overflow — Fix

Description

In wlan AP driver, there is a possible out of bounds write due to an incorrect bounds check. This could lead to remote (proximal/adjacent) escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00415809; Issue ID: MSV-3405.

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CVSS v3.1 Score

8.8

HIGH

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-120 CWE-120

Affected Products

Vendor	Product	Versions
mediatek	software_development_kit	< 7.6.7.2
mediatek	mt6890	All
mediatek	mt7915	All
mediatek	mt7916	All
mediatek	mt7981	All
mediatek	mt7986	All
openwrt	openwrt	All
openwrt	openwrt	All
mediatek	mt6890	All

References

Advisories & Patches

https://corp.mediatek.com/product-security-bulletin/October-2025

Frequently Asked Questions

What is CVE-2025-20709? +

In wlan AP driver, there is a possible out of bounds write due to an incorrect bounds check. This could lead to remote (proximal/adjacent) escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00415809; Issue ID: MSV-3405. It has a CVSS v3.1 base score of 8.8 (HIGH).

How severe is CVE-2025-20709? +

CVE-2025-20709 has a CVSS v3.1 score of 8.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-20709? +

CVE-2025-20709 affects products from mediatek, openwrt, specifically: mt6890, mt7915, mt7916, mt7981, mt7986, openwrt, software_development_kit. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-20709? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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