CVE-2026-49808
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 Windows Kernel allows an authorized attacker to elevate privileges 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 confidenceA race condition vulnerability exists in the Windows Kernel due to improper synchronization when accessing shared resources. An authorized local attacker can exploit timing-dependent behavior to manipulate kernel state and elevate privileges from their current user level to SYSTEM or administrator privileges.
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< 10.0.26100.8875< 10.0.26200.8875< 10.0.28000.2269< 10.0.28000.2525< 10.0.26100.33158CVSS 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
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/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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Check Windows build versionRun 'winver' or 'systeminfo | findstr /B /C:"OS Version"' to obtain the full build numberAffected if The displayed build number is lower than 10.0.26100.8875 for Windows 11 24h2, lower than 10.0.26200.8875 for Windows 11 25h2, lower than 10.0.28000.2269 or 10.0.28000.2525 for Windows 11 26h1, or lower than 10.0.26100.33158 for Windows Server 2025
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Confirm exact Windows editionRun 'systeminfo' and check the "OS Name" field to determine if the system is Windows 11 (and which feature update: 24h2, 25h2, or 26h1) or Windows Server 2025Affected if The system is any Windows 11 version 24h2, 25h2, or 26h1, or Windows Server 2025, with a build number below the corresponding threshold
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Verify kernel patch levelRun 'systeminfo' and check the "OS Build" number, or run 'winver' to see the full version string including the revision numberAffected if The OS build is lower than the specific threshold for that Windows edition or version
The system is affected if it runs Windows 11 24h2, 25h2, 26h1, or Windows Server 2025 with a build number below the specified thresholds for each version.
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 · scoped10.0.26100.887510.0.26100.3315810.0.26200.8875
Apply Microsoft security updates addressing Windows Kernel race conditions immediately; prioritize deployment on systems where untrusted local users have access, as this vulnerability enables privilege escalation.
Install Microsoft security patch for CVE-2026-49808 (KB reference needed from msrc.microsoft.com)
- Open Windows Settings and navigate to Windows Update
- Check for updates and install all available security updates
- Restart the system to apply the kernel update
- Verify the installed version matches or exceeds the fixed build: Windows 11 24h2 should be >= 10.0.26100.8875, Windows 11 25h2 should be >= 10.0.26200.8875, Windows 11 26h1 should be >= 10.0.28000.2525, Windows Server 2025 should be >= 10.0.26100.33158
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-49808 — 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-2026-49808 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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