dbcve.org
Windows 10 1507Operating system · Microsoft

CVE-2025-26634

HIGH · 7.5 CVSS v3.1 Published 2025-03-11
Fix available
A fix is available. Upgrade to 10.0.10240.20915 / 10.0.14393.7785 or later.
See remediation →
81/100
Remediation priority · High
Remotely reachable 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
Heap-based buffer overflow in Windows Core Messaging allows an authorized attacker to elevate privileges over a network.

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 heap-based buffer overflow vulnerability in Windows Core Messaging allows an authenticated attacker to execute code with elevated privileges. The flaw exists in the messaging infrastructure component that handles inter-process and network communication, where improper bounds checking during message processing enables memory corruption that can be exploited for local privilege escalation.

MitigationApply Microsoft security updates for Windows Core Messaging when available; until then, restrict network access to affected systems and minimize the attack surface by disabling unnecessary messaging services.

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 1507Operating system
Affected:< 10.0.10240.20915
Windows 10 1607Operating system
Affected:< 10.0.14393.7785
Windows 10 21h2Operating system
Affected:< 10.0.19044.5487
Windows 10 22h2Operating system
Affected:< 10.0.19045.5487
Windows 11 22h2Operating system
Affected:< 10.0.22621.4890
Windows 11 23h2Operating system
Affected:< 10.0.22631.4890
Windows 11 24h2Operating system
Affected:< 10.0.26100.3194
Windows Server 2016Operating system
Affected:< 10.0.14393.7785

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

CVSS:3.1/AV:N/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' from command prompt to obtain the full OS version build number
    Affected if The build number falls below any of these thresholds: 10240.20915 (1507), 14393.7785 (1607/Server 2016), 19044.5487 (21h2), 19045.5487 (22h2), 22621.4890 (11 22h2), 22631.4890 (11 23h2), 26100.3194 (11 24h2)
  2. Identify Windows release
    Run 'winver' to confirm the Windows 10 or 11 release (1507, 1607, 21h2, 22h2) or check systeminfo for Windows Server 2016
    Affected if The system is running an affected Windows 10 release, Windows 11 release, or Windows Server 2016 with a build number lower than the corresponding threshold for that release

The system is affected if it runs any Windows 10 version (1507, 1607, 21h2, 22h2), Windows 11 (22h2, 23h2, 24h2), or Windows Server 2016 with a build number lower than the specific threshold for that release, since the vulnerability exists in the Windows Core Messaging component present in these versions.

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 10.0.10240.20915 / 10.0.14393.7785 / 10.0.19044.5487 or later
Fixed in 10.0.10240.2091510.0.14393.778510.0.19044.5487
Interim mitigation

Apply Microsoft security updates for Windows Core Messaging when available; until then, restrict network access to affected systems and minimize the attack surface by disabling unnecessary messaging services.

Recommended fix High confidence

Update to Windows 10 1507 (10.0.10240.20915), Windows 10 1607 (10.0.14393.7785), Windows 10 21h2 (10.0.19044.5487), Windows 10 22h2 (10.0.19045.5487), Windows 11 22h2 (10.0.22621.4890), Windows 11 23h2 (10.0.22631.4890), Windows 11 24h2 (10.0.26100.3194), or Windows Server 2016 (10.0.14393.7785) res

  1. Identify the current Windows version by running 'winver' or 'systeminfo' from command prompt
  2. Determine which version range your current build falls into from the affected versions list
  3. Apply the latest Windows security update from Windows Update or Microsoft Update Catalog
  4. Alternatively, download and install the specific cumulative update that contains the fix for your Windows version
  5. Verify the installation was successful by checking the OS build number matches or exceeds the fixed version for your product
  6. Restart the system as required by the update installation
Caveat Standard Windows update apply; ensure backups and compatibility testing are performed for mission-critical systems before broad deployment

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

Fix this in Windows 10 1507 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing12.0 h
  • Review / QA6.0 h
30.0 hours of engineering $5,120
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $8,192.

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-2025-26634 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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