dbcve.org
Windows 10 1607Operating system · Microsoft

CVE-2026-34331

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
Concurrent execution using shared resource with improper synchronization ('race condition') 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 race condition vulnerability exists in the Windows Win32K graphics subsystem (GRFX) where improper synchronization of shared resources during concurrent execution allows a local authenticated attacker to elevate privileges to higher integrity levels on the affected system.

MitigationApply Microsoft security updates addressing this Win32K GRFX vulnerability; prioritize patching systems where local users have access as the attack requires local access. No network-based mitigation is applicable for this local privilege escalation.

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
    Open Command Prompt and run: systeminfo | findstr /C:"OS Version" /C:"Build"
    Affected if The displayed build number falls below any of the following thresholds: 14393.9140 (Win10 1607), 17763.8755 (Win10 1809), 19044.7291 (Win10 21h2/22h2), 22631.7079 (Win11 23h2), 26100.8390 (Win11 24h2/25h2), or 28000.2113 (Win11 26h1)
  2. Verify exact Windows release
    Run winver or check Start > Settings > System > About to confirm the Windows release (e.g., 22h2, 23h2, 24h2)
    Affected if The system is running an affected Windows 10 or Windows 11 release and the build number is below the corresponding threshold for that release
  3. Confirm Win32K component is present
    Verify the system has a graphical desktop environment (Win32K.sys loads on all Windows systems with GUI; server systems without Desktop Experience may have reduced attack surface)
    Affected if The system has a full Windows desktop environment with Win32K.sys loaded

A system is affected if it runs any Windows 10 version (1607, 1809, 21h2, 22h2) or Windows 11 version (23h2, 24h2, 25h2, 26h1) with a build number lower than the fixed threshold for that specific release.

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 Microsoft security updates addressing this Win32K GRFX vulnerability; prioritize patching systems where local users have access as the attack requires local access. No network-based mitigation is applicable for this local privilege escalation.

Recommended fix High confidence

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

  1. Open Windows Settings on the affected system
  2. Navigate to Update & Security > Windows Update
  3. Click 'Check for updates' to install the latest security updates
  4. Alternatively, manually download the specific security update from the Microsoft Update Catalog (catalog.update.microsoft.com) for your Windows version
  5. After installation, restart the system to apply the changes
  6. Verify the installed build version matches or exceeds the fixed version for your Windows release
Caveat Standard Windows update risks apply (potential for compatibility issues with legacy software) - test updates in staging environment before broad deployment

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
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.

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-2026-34331 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