365 AppsApplication · Microsoft

CVE-2026-20944

HIGH · 8.4 CVSS v3.1 Published 2026-01-13
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
89/100
Remediation priority · High
No privileges Zero-click

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 Microsoft Office Word allows an unauthorized 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 confidence

This is an out-of-bounds read vulnerability in Microsoft Office Word. The memory corruption issue can be triggered by a specially crafted Word document, allowing an attacker to execute code locally on the affected system without authorization.

MitigationApply the latest Microsoft security updates for Office Word to remediate this vulnerability. Until patched, avoid opening Word documents from untrusted or unknown sources.

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
365 AppsApplication
Affected:all versions
Office Long Term Servicing ChannelApplication
Affected:= 2021= 2024

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

CVSS:3.1/AV:L/AC:L/PR:N/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. Confirm Microsoft Word is installed
    Check for the presence of winword.exe on the system. Common locations: C:\Program Files\Microsoft Office\root\Office16\winword.exe or C:\Program Files (x86)\Microsoft Office\root\Office16\winword.exe. Also verify via Programs and Features in Control Panel looking for Microsoft Office or Microsoft Word.
    Affected if winword.exe is found on the system, indicating Word is installed
  2. Identify the installed Office/Word version
    Open Word, go to File > Account > About Word to see the version number. Alternatively, check the registry under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\ClickToRun\Configuration or HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\16.0\Common\InstallRoot for version details.
    Affected if Version is Microsoft 365 Apps (any version number), Office LTSC 2021, or Office LTSC 2024, which are all listed as affected
  3. Determine the Office update channel (for Microsoft 365)
    Check registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\ClickToRun\Configuration for the UpdateChannel value. For Microsoft 365, all channels are affected.
    Affected if UpdateChannel is present and running any Microsoft 365 channel, indicating a vulnerable configuration
  4. Verify default document handling behavior
    Confirm that Word is configured to open documents (the default state). This is the standard behavior and required for the vulnerability to be triggered.
    Affected if Word is able to open .docx or .doc files, which is the default configuration

If Microsoft Word is installed and the version is Microsoft 365 Apps (any version) or Office LTSC 2021/2024, the system is affected by this vulnerability when opening specially crafted Word documents.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the latest Microsoft security updates for Office Word to remediate this vulnerability. Until patched, avoid opening Word documents from untrusted or unknown sources.

Fix this in 365 Apps Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-20944 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-20944 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