dbcve.org
Windows 10 21h2Operating system · Microsoft

CVE-2026-45640

HIGH · 7.0 CVSS v3.1 Published 2026-06-09
Fix available
A fix is available. Upgrade to 10.0.19044.7417 / 10.0.19045.7417 or later.
See remediation →
72/100
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
Use after free in Windows Bluetooth Port Driver allows an authorized attacker to elevate privileges locally.

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 use-after-free vulnerability exists in the Windows Bluetooth Port Driver that allows a locally authorized attacker to execute code with elevated privileges. The flaw stems from improper memory management in the driver, where memory is accessed after being freed, leading to potential arbitrary code execution in kernel context.

MitigationApply the latest Microsoft security updates for Windows, specifically any patches addressing the Bluetooth Port Driver vulnerability. Until patches are available, minimize the attack surface by disabling Bluetooth if not required.

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
Windows 10 21h2Operating system
Affected:< 10.0.19044.7417
Windows 10 22h2Operating system
Affected:< 10.0.19045.7417
Windows 11 23h2Operating system
Affected:< 10.0.22631.7219
Windows 11 24h2Operating system
Affected:< 10.0.26100.8655
Windows 11 25h2Operating system
Affected:< 10.0.26200.8655
Windows 11 26h1Operating system
Affected:< 10.0.28000.2269
Windows Server 2022Operating system
Affected:< 10.0.20348.5256
Windows Server 2025Operating system
Affected:< 10.0.26100.32995

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

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/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. Check Windows version and build number
    Run 'winver' from the Run dialog or execute 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' in Command Prompt. Note the full build number (e.g., 10.0.19045.7417).
    Affected if The installed build number is lower than the threshold for your Windows version: 19044.7417 (21h2), 19045.7417 (22h2), 22631.7219 (23h2), 26100.8655 (24h2), 26200.8655 (25h2), 28000.2269 (26h1), 20348.5256 (Server 2022), or 26100.32995 (Server 2025).
  2. Identify the Bluetooth Port Driver version
    Open Device Manager, expand 'Bluetooth', right-click 'Microsoft Bluetooth Enumerator' or the Bluetooth Radio device, select Properties, go to the Driver tab, and note the Driver Version. Alternatively, run 'driverquery /v | findstr -i bluetooth' in an elevated Command Prompt.
    Affected if The Bluetooth Port Driver (bthport.sys or related) is present and the version cannot be verified against the patched build, indicating the system likely has the vulnerable driver.
  3. Confirm Bluetooth is configured on the system
    Open Settings > Bluetooth & devices (or run 'ms-settings:bluetooth' from Run). Check if any Bluetooth devices are paired or if Bluetooth is turned on. In PowerShell, run 'Get-PnpDevice -Class Bluetooth | Select-Object Status, FriendlyName'.
    Affected if Bluetooth is enabled or has been used, meaning the vulnerable driver code path could be exercised.

You are affected if your Windows build is below the threshold for your specific version AND the Bluetooth Port Driver is present and Bluetooth functionality is or was enabled on the system.

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.

dbcve · scoped
Upgrade available Upgrade to 10.0.19044.7417 / 10.0.19045.7417 / 10.0.20348.5256 or later
Fixed in 10.0.19044.741710.0.19045.741710.0.20348.5256
Interim mitigation

Apply the latest Microsoft security updates for Windows, specifically any patches addressing the Bluetooth Port Driver vulnerability. Until patches are available, minimize the attack surface by disabling Bluetooth if not required.

Recommended fix High confidence

Microsoft Security Update (specific KB per Windows version - see steps above for build numbers)

  1. 1. Identify the exact Windows version and build number by running `winver` or `systeminfo`
  2. 2. Check current installed build: open Settings > Windows Update > View update history
  3. 3. For Windows 10 21h2: Apply KB5061533 (build 10.0.19044.7417) or later
  4. 4. For Windows 10 22h2: Apply KB5061538 (build 10.0.19045.7417) or later
  5. 5. For Windows 11 23h2: Apply KB5061419 (build 10.0.22631.7219) or later
  6. 6. For Windows 11 24h2: Apply KB5061539 (build 10.0.26100.8655) or later
  7. 7. For Windows 11 25h2: Apply KB5061550 (build 10.0.26200.8655) or later
  8. 8. For Windows 11 26h1: Apply KB5061553 (build 10.0.28000.2269) or later
Caveat Standard Windows update risks - ensure backups and test in staging if possible

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Windows 10 21h2 Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
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Scan for this in your stack

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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-2026-45640 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