CVE-2026-20456

Description

In wlan STA driver, there is a possible system crash due to a missing bounds check. This could lead to local denial of service with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00480851; Issue ID: MSV-6338.

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CVSS v3.1 Score

5.5

MEDIUM

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

EPSS — Exploit Prediction

0.0010

Probability of exploitation

0.01%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
mediatek	mt7902_firmware	All
mediatek	mt7902	All
mediatek	mt7920_firmware	All
mediatek	mt7920	All
mediatek	mt7921_firmware	All
mediatek	mt7921	All
mediatek	mt7922_firmware	All
mediatek	mt7922	All
mediatek	mt7925_firmware	All
mediatek	mt7925	All
mediatek	mt7927_firmware	All
mediatek	mt7927	All

References

Advisories & Patches

https://corp.mediatek.com/product-security-bulletin/June-2026

Frequently Asked Questions

What is CVE-2026-20456? +

In wlan STA driver, there is a possible system crash due to a missing bounds check. This could lead to local denial of service with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00480851; Issue ID: MSV-6338. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2026-20456? +

CVE-2026-20456 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0010, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-20456? +

CVE-2026-20456 affects products from mediatek, specifically: mt7902, mt7902_firmware, mt7920, mt7920_firmware, mt7921, mt7921_firmware, mt7922, mt7922_firmware, mt7925, mt7925_firmware, mt7927, mt7927_firmware. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-20456? +

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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