dbcve.org
Windows 10 1607Operating system · Microsoft

CVE-2026-34334

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 TCP/IP 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 TCP/IP stack where improper synchronization of shared resources allows a local, authorized attacker to gain elevated privileges. The flaw occurs during concurrent execution scenarios within the networking subsystem.

MitigationApply Microsoft security updates for Windows when released; limit local system access to trusted, authorized users to reduce the attack surface for this privilege escalation vector.

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
    Run 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to determine the installed Windows version and build number
    Affected if The build number falls below any of these thresholds: 14393.9140 (Windows 10 1607), 17763.8755 (Windows 10 1809), 19044.7291 (Windows 10 21h2/22h2), 22631.7079 (Windows 11 23h2), 26100.8390 (Windows 11 24h2), 26200.8390 (Windows 11 25h2), or 28000.2113 (Windows 11 26h1)
  2. Confirm TCP/IP stack is present
    Verify the TCP/IP protocol stack is enabled by checking network adapter status or running 'netsh interface show interface'
    Affected if TCP/IP networking is enabled (which is the default state for virtually all Windows installations)

The system is affected if it runs any Windows 10 or 11 version with a build number lower than the thresholds listed above, combined with TCP/IP networking being active.

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 for Windows when released; limit local system access to trusted, authorized users to reduce the attack surface for this privilege escalation vector.

Recommended fix High confidence

Upgrade to 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 lat

  1. Identify the current Windows version by running 'winver' or checking System Information
  2. Determine which Windows 10 or 11 version family your system is running (1607, 1809, 21h2, 22h2, 23h2, 24h2, 25h2, or 26h1)
  3. Open Windows Update by pressing Win+I and navigating to Windows Update
  4. Click 'Check for updates' and install all available updates
  5. Alternatively, manually download and install the specific cumulative update for your Windows version from the Microsoft Update Catalog
  6. After installation, restart the computer to apply the security update
  7. Verify the update was installed by checking Windows Update history or running 'winver' to confirm the version matches or exceeds the fixed version for your build
Caveat Standard Windows cumulative 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
  • Implementation2.0 h
  • Testing8.0 h
  • Review / QA4.0 h
18.0 hours of engineering $3,080
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,928.

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-2026-34334 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