dbcve.org
Windows 10 1607Operating system · Microsoft

CVE-2026-27917

HIGH · 7.0 CVSS v3.1 Published 2026-04-14
Fix available
A fix is available. Upgrade to 10.0.14393.9060 / 10.0.17763.8644 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 WFP NDIS Lightweight Filter Driver (wfplwfs.sys) 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 in the Windows Filtering Platform NDIS Lightweight Filter Driver (wfplwfs.sys) allows a locally authorized attacker to exploit freed memory after deallocation, potentially achieving elevated privileges on the affected system.

MitigationApply Microsoft security updates for this vulnerability once available through Windows Update; verify the wfplwfs.sys driver version and consider restricting access to the driver or disabling the Windows Filtering Platform component if an immediate patch is unavailable.

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 1607Operating system
Affected:< 10.0.14393.9060
Windows 10 1809Operating system
Affected:< 10.0.17763.8644
Windows 10 21h2Operating system
Affected:< 10.0.19044.7184
Windows 10 22h2Operating system
Affected:< 10.0.19045.7184
Windows 11 23h2Operating system
Affected:< 10.0.22631.6936
Windows 11 24h2Operating system
Affected:< 10.0.26100.8246
Windows 11 25h2Operating system
Affected:< 10.0.26200.8246
Windows 11 26h1Operating system
Affected:< 10.0.28000.1836

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. Verify wfplwfs.sys driver exists
    Open File Explorer and navigate to C:\Windows\System32\drivers\, or run 'dir C:\Windows\System32\drivers\wfplwfs.sys' in Command Prompt
    Affected if The file does not exist - the driver is not installed, so the vulnerability does not apply
  2. Check Windows build version
    Run 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to identify your Windows edition and build number
    Affected if The build number falls within any of the affected version ranges listed in the CVE (for example, Windows 10 1809 builds earlier than 10.0.17763.8644)
  3. Retrieve wfplwfs.sys driver version
    Right-click wfplwfs.sys in C:\Windows\System32\drivers\, select Properties, then Details tab; or run 'powershell (Get-Item C:\Windows\System32\drivers\wfplwfs.sys).VersionInfo'
    Affected if The File version is lower than the threshold for your Windows build (for example, below 10.0.14393.9060 for Windows 10 1607)
  4. Confirm Windows Filtering Platform is enabled
    Run 'sc query wfplwfs' in Command Prompt or check Services list for Windows Filtering Platform NDIS Lightweight Filter
    Affected if The service state shows as RUNNING, indicating the vulnerable driver is active

You are affected if your Windows build matches one of the listed versions AND the wfplwfs.sys version is below the specified threshold AND the Windows Filtering Platform NDIS Lightweight Filter service is running.

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 10.0.14393.9060 / 10.0.17763.8644 / 10.0.19044.7184 or later
Fixed in 10.0.14393.906010.0.17763.864410.0.19044.7184
Interim mitigation

Apply Microsoft security updates for this vulnerability once available through Windows Update; verify the wfplwfs.sys driver version and consider restricting access to the driver or disabling the Windows Filtering Platform component if an immediate patch is unavailable.

Recommended fix High confidence

Windows 10 1607: 10.0.14393.9060 | Windows 10 1809: 10.0.17763.8644 | Windows 10 21h2: 10.0.19044.7184 | Windows 10 22h2: 10.0.19045.7184 | Windows 11 23h2: 10.0.22631.6936 | Windows 11 24h2: 10.0.26100.8246 | Windows 11 25h2: 10.0.26200.8246 | Windows 11 26h1: 10.0.28000.1836

  1. Verify current Windows build version by running 'winver' or 'systeminfo | findstr /B /C:"OS Build"'
  2. Backup critical data before initiating the update
  3. Apply the appropriate Windows security update for your version from Windows Update or Microsoft Update Catalog
  4. Restart the system after the update completes
  5. Verify the build number matches or exceeds the fixed version for your Windows release
Caveat Standard Windows update; no breaking changes expected for this security patch

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

Fix this in Windows 10 1607 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation1.0 h
  • Testing3.0 h
  • Review / QA2.0 h
10.0 hours of engineering $1,790
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,864.

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-2026-27917 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