dbcve.org
Windows 10 1607Operating system · Microsoft

CVE-2026-49792

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 Patch available 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
Numeric truncation error in Windows Resilient File System (ReFS) allows an authorized attacker to execute code locally.

In the news

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

A numeric truncation error in Windows Resilient File System (ReFS) allows a local, authorized attacker to execute arbitrary code. This type of vulnerability occurs when a larger integer value is truncated to a smaller type, potentially causing integer overflow conditions that can lead to memory corruption and code execution in kernel context.

MitigationApply Microsoft security updates for Windows ReFS when available. Until a patch is released, minimize local privileged access and monitor for suspicious kernel-level activity.

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:< 10.0.28000.2269< 10.0.28000.2525
Windows Server 2016Operating system
Affected:< 10.0.14393.9339

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. Check if ReFS volumes exist on the system
    Open PowerShell and run: Get-Volume | Where-Object {$_.FileSystem -eq 'ReFS'} to list any ReFS-formatted volumes
    Affected if The system has one or more ReFS-formatted volumes (vulnerability only applies when ReFS is in use)
  2. Identify the installed Windows 10 build version
    Run 'winver' or execute in PowerShell: [System.Environment]::OSVersion.Version.ToString() and also check registry key HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\CurrentBuild for the full build number
    Affected if Windows 10 build is below 14393.9339 (1607), 17763.9020 (1809), 19044.7548 (21h2), or 19045.7548 (22h2)
  3. Identify the installed Windows 11 build version
    Run 'winver' or execute in PowerShell: [System.Environment]::OSVersion.Version.ToString() and also check registry key HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\CurrentBuild for the full build number
    Affected if Windows 11 build is below 26100.8875 (24h2), 26200.8875 (25h2), or 28000.2525/28000.2269 (26h1)
  4. Identify the installed Windows Server build version
    Run 'winver' or execute in PowerShell: [System.Environment]::OSVersion.Version.ToString() and check registry key HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\CurrentBuild for the full build number
    Affected if Windows Server 2016 build is below 10.0.14393.9339

The system is affected if it has ReFS-formatted volumes AND is running a Windows version below the fixed build numbers for the respective release (10.0.14393.9339, 17763.9020, 19044.7548, 19045.7548, 26100.8875, 26200.8875, or 28000.2525).

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.

From vendor data
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
Vendor patch msrc.microsoft.com →
Interim mitigation

Apply Microsoft security updates for Windows ReFS when available. Until a patch is released, minimize local privileged access and monitor for suspicious kernel-level activity.

Fix this in Windows 10 1607 Scoped from the published advisory
  • Consultation6.0 h
  • Implementation48.0 h
  • Testing24.0 h
  • Review / QA12.0 h
90.0 hours of engineering $15,600
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $24,960.

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-2026-49792 in production — separate from our analysis above.

No notes yet

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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