CVE-2025-55226
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 · uneditedConcurrent execution using shared resource with improper synchronization ('race condition') in Graphics Kernel allows an authorized attacker to execute code 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 confidenceA race condition vulnerability exists in the Graphics Kernel where concurrent execution accesses a shared resource without proper synchronization. An authorized local attacker can exploit this to execute arbitrary code. The vulnerability stems from inadequate locking mechanisms around shared data structures in the graphics subsystem.
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< 10.0.10240.21128< 10.0.14393.8422< 10.0.17763.7792< 10.0.19044.6332< 10.0.19045.6332< 10.0.22621.5909< 10.0.22631.5909< 10.0.26100.6508CVSS 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
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/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 checksWork through these to decide whether this CVE applies to you.
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Verify Windows build versionRun 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to display the installed Windows version and build numberAffected if The build number falls below any of these thresholds: 10240.21128 (Win10 1507), 14393.8422 (Win10 1607), 17763.7792 (Win10 1809), 19044.6332 (Win10 21h2), 19045.6332 (Win10 22h2), 22621.5909 (Win11 22h2), 22631.5909 (Win11 23h2), or 26100.6508 (Win11 24h2)
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Confirm Windows edition matches affected listRun 'winver' or check System Properties to confirm whether the installed Windows edition (Home, Pro, Enterprise, etc.) corresponds to one of the affected versions listedAffected if The system runs an affected Windows 10 or Windows 11 edition with a vulnerable build number from step 1
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Identify Graphics Kernel componentCheck for the presence of win32k.sys by running 'driverquery /v | findstr win32k' or examining C:\Windows\System32\win32k.sys through File Explorer propertiesAffected if The win32k.sys file exists on the system, as the vulnerability resides in this Graphics Kernel component
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Check for recent graphics kernel updatesRun 'powershell Get-HotFix | Sort-Object InstalledOn -Descending | Select-Object -First 10' to list recently installed updates, or check Windows Update history for security updates related to the graphics subsystemAffected if No recent security updates addressing graphics kernel race conditions have been installed, and the build version remains in the vulnerable range
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Verify local attacker threat contextAssess whether untrusted local users or processes have access to the system, as exploitation requires an authorized local attacker to trigger the race condition in the graphics subsystemAffected if The system allows local user access or runs untrusted code that could trigger the race condition in the Graphics Kernel
The system is affected if it runs any of the specified Windows 10 or Windows 11 versions with build numbers lower than the patched thresholds listed, and the Graphics Kernel (win32k.sys) component is present.
Generated from the published advisory. Verify against your own configuration.
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 · scoped10.0.10240.2112810.0.14393.842210.0.17763.7792
Implement proper synchronization primitives (mutexes, spinlocks, or atomic operations) around all shared resource accesses in the Graphics Kernel. Apply vendor-provided patches and conduct thorough concurrency testing to verify the fix.
Windows Security Update containing CVE-2025-55226 fix (builds listed above or higher)
- Open Settings > Update & Security > Windows Update and check for updates
- Install any available security updates for Windows
- After updates are installed, verify the system is running a build number equal to or higher than: 10.0.10240.21128 (Win10 1507), 10.0.14393.8422 (Win10 1607), 10.0.17763.7792 (Win10 1809), 10.0.19044.6332 (Win10 21h2), 10.0.19045.6332 (Win10 22h2), 10.0.22621.5909 (Win11 22h2), 10.0.22631.5909 (Win11 23h2), or 10.0.26100.6508 (Win11 24h2)
- To check the build number, run 'winver' or 'systeminfo' from command prompt
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation8.0 h
- Implementation24.0 h
- Testing16.0 h
- Review / QA8.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $15,616.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2025-55226 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2025-55226 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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
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