Nbiot SdkApplication · Mediatek

CVE-2025-20687

MEDIUM · 5.5 CVSS v3.1 Published 2025-07-08
Fix available
A fix is available. Upgrade to after 3.6 or later.
See remediation →
57/100
Remediation priority · Elevated
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 Bluetooth driver, there is a possible out of bounds read due to an incorrect bounds check. This could lead to local denial of service with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: WCNCR00418045; Issue ID: MSV-3481.

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 · high confidence

A Bluetooth driver vulnerability involving an out of bounds read due to an incorrect bounds check. The flaw allows local denial of service via user execution privileges without requiring user interaction. The issue is addressed by vendor patch WCNCR00418045.

MitigationApply the vendor-supplied patch (WCNCR00418045) to the Bluetooth driver firmware/software. Verify the update does not introduce regressions in Bluetooth functionality.

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:<= 3.6

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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 version
    Check your project's SDK version by reviewing the SDK release notes, firmware metadata, or build configuration files that reference the Mediatek NBIoT SDK version
    Affected if SDK version is 3.6 or lower (any version <= 3.6)
  2. Verify Bluetooth functionality is in use
    Determine if your device or application utilizes the Bluetooth driver component from the Mediatek NBIoT SDK. Check runtime configuration, device logs, or firmware feature flags that enable Bluetooth.
    Affected if Bluetooth driver is enabled and actively used
  3. Check for vendor patch WCNCR00418045
    Review firmware changelogs, patch applied records, or contact Mediatek to verify if the WCNCR00418045 patch has been applied to the Bluetooth driver code
    Affected if Patch WCNCR00418045 has NOT been applied to the Bluetooth driver
  4. Confirm the out-of-bounds read condition
    Monitor system stability and Bluetooth operation logs for crash events, memory access errors, or unexpected termination that may indicate the vulnerability is being triggered
    Affected if Bluetooth driver crashes or stability issues occur without other known causes

A defender is affected if they are using Mediatek NBIoT SDK version 3.6 or lower with Bluetooth enabled and without the WCNCR00418045 patch applied to the Bluetooth driver.

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 3.6
Interim mitigation

Apply the vendor-supplied patch (WCNCR00418045) to the Bluetooth driver firmware/software. Verify the update does not introduce regressions in Bluetooth functionality.

Fix this in Nbiot Sdk Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,580
Get the upgrade done

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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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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-2025-20687 in production — separate from our analysis above.

No notes yet

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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