CVE-2026-20423
Out-of-Bounds Write in WLAN STA Driver Enables Privilege Escalation
Publication date: 2026-03-02
Last updated on: 2026-03-03
Assigner: MediaTek, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| mediatek | nbiot_sdk | to 3.8 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-787 | The product writes data past the end, or before the beginning, of the intended buffer. |
| CWE-749 | The product provides an Applications Programming Interface (API) or similar interface for interaction with external actors, but the interface includes a dangerous method or function that is not properly restricted. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
CVE-2026-20423 is a high-severity vulnerability in the wlan STA driver of MediaTek chipsets. It is caused by a missing bounds check which leads to a possible out-of-bounds write. This means that the software does not properly validate input or memory boundaries, potentially causing memory corruption.
The vulnerability falls under CWE-749 (Exposed Dangerous Method or Function) and affects several MediaTek chipsets including MT7902, MT7920, MT7921, MT7922, MT7925, and MT7927.
Exploitation requires only user execution privileges and does not need user interaction, which means an attacker with local access could escalate their privileges on the device.
How can this vulnerability impact me? :
This vulnerability can lead to local escalation of privilege, allowing an attacker with user-level execution privileges to gain higher privileges on the affected device.
Because it involves a possible out-of-bounds write, it could also cause memory corruption, which might lead to system instability or further security issues.
No user interaction is needed for exploitation, increasing the risk if an attacker has local access.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, apply the patch identified as WCNCR00465314 provided by MediaTek.
Ensure your devices using MediaTek chipsets MT7902, MT7920, MT7921, MT7922, MT7925, and MT7927 are updated with the latest firmware from the device OEMs.
Monitor official MediaTek security bulletins for any further updates or mitigation advice.