dbcve.org
Windows 10 1607Operating system · Microsoft

CVE-2026-50491

HIGH · 7.8 CVSS v3.1 Published 2026-07-14
Fix available
A fix is available. Upgrade to 10.0.14393.9339 / 10.0.17763.9020 or later.
See remediation →
80/100
Remediation priority · High
Zero-click 5 weeks old

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
Out-of-bounds read in Code Integrity DLL (ci.dll) allows an authorized attacker to elevate privileges locally.

In the news

Third-party coverage
Trending covered by 1 outlet this week · latest 1mo ago

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 confidence

Out-of-bounds read vulnerability in Windows Code Integrity DLL (ci.dll) allows a locally authenticated attacker to read sensitive memory contents and potentially elevate privileges to higher integrity levels.

MitigationApply Microsoft security updates for CVE-2026-50491 once released; verify code integrity module version and ensure Windows Update is functioning properly.

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:< 10.0.14393.9339
Windows 10 1809Operating system
Affected:< 10.0.17763.9020
Windows 10 21h2Operating system
Affected:< 10.0.19044.7548
Windows 10 22h2Operating system
Affected:< 10.0.19045.7548
Windows 11 24h2Operating system
Affected:< 10.0.26100.8875
Windows 11 25h2Operating system
Affected:< 10.0.26200.8875
Windows 11 26h1Operating system
Affected:< 10.0.28000.2525
Windows Server 2012Operating system
Affected:all versions= r2

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

CVSS:3.1/AV:L/AC:L/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. Determine Windows build version
    Run 'winver' from command prompt or check System Properties, or use 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"'
    Affected if Build number is below 14393.9339 (Win10 1607), 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); or if running Server 2012/R2 (all versions)
  2. Confirm ci.dll file version
    Locate ci.dll in C:\Windows\System32\ or C:\Windows\SysWOW64\, right-click and select Properties > Details, or run 'powershell (Get-Item "C:\Windows\System32\ci.dll").VersionInfo'
    Affected if File version is lower than the build-specific thresholds listed in step 1 (this correlates with the vulnerable builds)
  3. Verify current user context
    Run 'whoami /all' or 'whoami' to confirm current user privileges
    Affected if User has local account access but is not running at high integrity level (vulnerability requires locally authenticated attacker, lower-privileged account)
  4. Check if Code Integrity policy is enforced
    Run 'powershell Get-CimInstance -ClassName Win32_ComputerSystem | Select-Object -Property DomainRole, PartOfDomain' to understand the system role; Code Integrity is always active on modern Windows but policy strictness varies
    Affected if System is running with default Code Integrity settings (vulnerable component ci.dll is always loaded regardless of policy mode)

System is affected if running any Windows version or Server 2012/R2 build below the threshold build numbers listed in step 1, as ci.dll contains the vulnerable out-of-bounds read code in those 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 10.0.14393.9339 / 10.0.17763.9020 / 10.0.19044.7548 or later
Fixed in 10.0.14393.933910.0.17763.902010.0.19044.7548
Interim mitigation

Apply Microsoft security updates for CVE-2026-50491 once released; verify code integrity module version and ensure Windows Update is functioning properly.

Recommended fix High confidence

Windows 10 1607: build 10.0.14393.9339 | Windows 10 1809: build 10.0.17763.9020 | Windows 10 21h2: build 10.0.19044.7548 | Windows 10 22h2: build 10.0.19045.7548 | Windows 11 24h2: build 10.0.26100.8875 | Windows 11 25h2: build 10.0.26200.8875 | Windows 11 26h1: build 10.0.28000.2525 | Windows Serve

  1. Open Windows Update (Settings > Update & Security > Windows Update) and check for updates
  2. Install all pending security updates
  3. After updating, verify the installed version by running 'winver' or 'systeminfo' and confirm the build number matches or exceeds the fixed version for your Windows release
  4. For Windows Server 2012/R2, as these versions are end-of-life with no patches available, consider migrating to a supported Windows Server version (e.g., Windows Server 2019, 2022, or 2025)
Caveat Windows Server 2012/R2 is end-of-life with no security updates; continuing use poses significant risk. Ensure application compatibility before upgrading to newer Windows versions.

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

Fix this in Windows 10 1607 Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
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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-2026-50491 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