CVE-2026-50409
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 · uneditedExposure of sensitive information to an unauthorized actor in Windows Overlay Filter allows an authorized attacker to disclose information locally.
In the news
Third-party coverage- Microsoft July 2026 Patch Tuesday fixes massive 570 flaws, 3 zero-days
- Microsoft CVE Summary - Bleeping Computer
Surfaced from public web coverage — external links open in a new tab.
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 confidenceWindows Overlay Filter contains a vulnerability that allows an authorized local attacker to access sensitive information they should not have access to. This is a local information disclosure issue where the attacker already has some level of authorized access to the system but can exploit the filter to read beyond their permitted scope.
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< 10.0.14393.9339< 10.0.17763.9020< 10.0.19044.7548< 10.0.19045.7548< 10.0.26100.8875< 10.0.26200.8875< 10.0.28000.2525< 10.0.14393.9339CVSS 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
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
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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Check your Windows version and build numberRun 'winver' or 'systeminfo | findstr /B /C:"OS Version"' to see the full version string, or run 'ver' at command promptAffected if The build number is lower than any of these thresholds: 14393.9339 (Win10 1607/Server 2016), 17763.9020 (Win10 1809), 19044.7548 (Win10 21h2), 19045.7548 (Win10 22h2), 26100.8875 (Win11 24h2), 26200.8875 (Win11 25h2), or 28000.2525 (Win11 26h1)
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Confirm Windows Overlay Filter component is presentCheck for the presence of the Overlay Filter driver by running 'fltmc filters' at an elevated command prompt to list loaded filter driversAffected if The Overlay Filter appears in the list of loaded filters (this component must be present for the vulnerability to be exploitable)
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Verify the filter driver is actively loadedRun 'fltmc filters' and confirm the Overlay Filter status shows as 'Active' rather than 'Unloaded'Affected if The Overlay Filter driver is loaded and active in memory
You are affected if your Windows build number falls below the thresholds listed AND the Windows Overlay Filter component is present and loaded on your system.
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 · scoped10.0.14393.933910.0.17763.902010.0.19044.7548
Apply Microsoft security updates for Windows Overlay Filter as they become available. Until a patch is released, restrict local access to sensitive systems and monitor for unusual file system or filter driver activity.
Install the latest Windows cumulative security updates for your specific Windows version from Microsoft Update. Fixed versions are: Windows 10 1607/Server 2016: 10.0.14393.9339, Windows 10 1809: 10.0.17763.9020, Windows 10 21h2: 10.0.19044.7548, Windows 10 22h2: 10.0.19045.7548, Windows 11 24h2: 10.
- Open Windows Settings and navigate to Update & Security > Windows Update
- Click 'Check for updates' to download and install the latest security updates
- Alternatively, manually download the appropriate cumulative update for your Windows version from the Microsoft Update Catalog (catalog.update.microsoft.com)
- Restart the system after updates are installed to complete the remediation
- Verify the installed OS version matches or exceeds the fixed version number for your release (e.g., for Windows 10 22h2, verify version is 10.0.19045.7548 or later)
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation2.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,832.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-50409 — 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-2026-50409 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
- No spam, self-promotion, credentials, or personal data