dbcve.org
Windows 10 1607Operating system · Microsoft

CVE-2026-34347

HIGH · 7.0 CVSS v3.1 Published 2026-05-12
Fix available
A fix is available. Upgrade to 10.0.14393.9140 / 10.0.17763.8755 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 Win32K - GRFX 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 Win32K kernel-mode graphics subsystem (GRFX) allows a locally authenticated attacker to corrupt memory and elevate privileges to SYSTEM level. The flaw exists in how the graphics driver handles freed memory objects.

MitigationApply the Microsoft security update for this vulnerability once released. Until then, minimize attack surface by restricting user privileges and monitoring for suspicious graphics driver activity.

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:< 10.0.14393.9140
Windows 10 1809Operating system
Affected:< 10.0.17763.8755
Windows 10 21h2Operating system
Affected:< 10.0.19044.7291
Windows 10 22h2Operating system
Affected:< 10.0.19045.7291
Windows 11 23h2Operating system
Affected:< 10.0.22631.7079
Windows 11 24h2Operating system
Affected:< 10.0.26100.8390
Windows 11 25h2Operating system
Affected:< 10.0.26200.8390
Windows 11 26h1Operating system
Affected:< 10.0.28000.2113

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 Start menu or execute 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' in Command Prompt
    Affected if The build number displayed is lower than any of the affected version thresholds (10.0.14393.9140, 10.0.17763.8755, 10.0.19044.7291, 10.0.19045.7291, 10.0.22631.7079, 10.0.26100.8390, 10.0.26200.8390, or 10.0.28000.2113)
  2. Confirm exact build version via PowerShell
    Run 'Get-ComputerInfo | Select-Object WindowsVersion, OsHardwareAbstractionLayer' in PowerShell to get precise build details
    Affected if The WindowsVersion value is below the fixed build numbers for your Windows release branch
  3. Identify Windows release branch
    Run 'winver' or check Settings > System > About to determine if you are on 1607, 1809, 21h2, 22h2, 23h2, 24h2, 25h2, or 26h1
    Affected if Your system is on any of the listed Windows 10 or Windows 11 releases with a build number lower than the corresponding fixed version
  4. Verify Win32K graphics subsystem is active
    Check for win32k.sys driver loaded: run 'driverquery /v | findstr win32k' in Command Prompt
    Affected if The win32k.sys driver is present (this is default in all affected Windows versions)
  5. Confirm Windows Update patch status
    Run 'Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 10' in PowerShell to list recent security updates
    Affected if No recent security update addressing this Win32K vulnerability has been installed, or the installed build remains below the fixed version thresholds

A system is affected if it runs any Windows 10 or Windows 11 version with a build number lower than the fixed version for that release branch, as listed in the affected products range.

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 10.0.14393.9140 / 10.0.17763.8755 / 10.0.19044.7291 or later
Fixed in 10.0.14393.914010.0.17763.875510.0.19044.7291
Interim mitigation

Apply the Microsoft security update for this vulnerability once released. Until then, minimize attack surface by restricting user privileges and monitoring for suspicious graphics driver activity.

Recommended fix High confidence

Windows 10 1607: 10.0.14393.9140 or later | Windows 10 1809: 10.0.17763.8755 or later | Windows 10 21h2: 10.0.19044.7291 or later | Windows 10 22h2: 10.0.19045.7291 or later | Windows 11 23h2: 10.0.22631.7079 or later | Windows 11 24h2: 10.0.26100.8390 or later | Windows 11 25h2: 10.0.26200.8390 or

  1. 1. Identify the current Windows version by running 'winver' or checking System Properties
  2. 2. Determine which Windows 10 or 11 version and build is installed (e.g., 10.0.19045.xxxx for Windows 10 22h2)
  3. 3. Navigate to Windows Update Settings or use Windows Server Update Services (WSUS) for enterprise deployments
  4. 4. Check for and install the latest security updates from Microsoft Update Catalog
  5. 5. Alternatively, download the appropriate security update from Microsoft Update Catalog directly using the KB number for this CVE
  6. 6. Restart the system after applying the update
  7. 7. Verify the build number has been updated to the fixed version or higher using 'winver'
Caveat Standard Windows security update - minimal risk of breaking changes; ensure backups and test in staging if applicable for enterprise environments

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

Fix this in Windows 10 1607 Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,980
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Scan for this in your stack

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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-2026-34347 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