dbcve.org
Nbiot SdkApplication · Mediatek

CVE-2026-20407

CRITICAL · 9.3 CVSS v3.1 Published 2026-02-02
Fix available
A fix is available. Upgrade to after 3.8 or later.
See remediation →
98/100
Remediation priority · Urgent
No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In wlan STA driver, there is a possible escalation of privilege due to a missing bounds check. This could lead to local escalation of privilege with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00464377; Issue ID: MSV-4905.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A missing bounds check in the wlan STA (Wireless LAN Station) driver allows a local attacker with User execution privileges to escalate privileges to a higher level. The vulnerability does not require user interaction to exploit. The patch ID WCNCR00464377 addresses this vulnerability.

MitigationApply the vendor patch WCNCR00464377 to update the wlan STA driver to a version containing the bounds check fix. Prioritize patching on systems where untrusted local users have access.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Nbiot SdkApplication
Affected:<= 3.8

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Mediatek Nbiot SDK installation
    Search for Mediatek Nbiot SDK components on the system. Check common installation directories such as /opt/mediatek-nbiot, /usr/local/mediatek, or within project dependencies. Look for SDK libraries, headers, or binary files containing 'nbiot' or 'mediatek' in their names.
    Affected if The Mediatek Nbiot SDK is present on the system and contains the wlan STA driver component.
  2. Determine the installed SDK version
    Locate the SDK version file or package metadata. Common locations include version.h, package.json, SDK release notes, or the SDK manifest. Run 'grep -r "3.8"' or check for a version configuration file within the SDK directory.
    Affected if The installed SDK version is 3.8 or earlier, placing it within the affected range <= 3.8.
  3. Locate the wlan STA driver component
    Search for the wlan STA driver files within the SDK. Look for files named wlan_sta, wlan_driver, or similar wireless station driver components. Check directories such as driver/, wireless/, or wifi/ within the SDK structure.
    Affected if The wlan STA driver module exists in the SDK and is available for use in the environment.
  4. Check if the system uses the vulnerable driver
    Identify if any running processes or configurations reference the wlan STA driver. Look for configuration files, initialization scripts, or runtime logs that load or reference the wireless station driver functionality.
    Affected if The wlan STA driver is loaded, referenced in configurations, or used by any application on the system.
  5. Verify patch application status
    Search for indicators that patch WCNCR00464377 has been applied. Check SDK release notes, patch history, or version changelogs for mentions of WCNCR00464377 or bounds check fixes in the wlan driver.
    Affected if No evidence exists that patch WCNCR00464377 has been applied, indicating the vulnerability remains unpatched.

The system is affected if Mediatek Nbiot SDK version 3.8 or earlier is installed, contains the wlan STA driver component, and the WCNCR00464377 patch has not been applied.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to a release after 3.8
Interim mitigation

Apply the vendor patch WCNCR00464377 to update the wlan STA driver to a version containing the bounds check fix. Prioritize patching on systems where untrusted local users have access.

Fix this in Nbiot Sdk Scoped from the published advisory
  • Consultation3.0 h
  • Implementation2.0 h
  • Testing3.0 h
  • Review / QA2.0 h
10.0 hours of engineering $1,770
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,832.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-20407 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-20407 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data