MSRC_CVE-2026-40418

Vulnerability from csaf_microsoft - Published: 2026-05-12 07:00 - Updated: 2026-05-12 07:00
Summary
Microsoft Office Click-To-Run Elevation of Privilege Vulnerability
Severity
Important
Notes
Additional Resources: To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle
Disclaimer: The information provided in the Microsoft Knowledge Base is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
Customer Action: Required. The vulnerability documented by this CVE requires customer action to resolve.
CWE-416 - Use After Free
Affected products
Product Identifier Version Remediation
Microsoft Office 2019 for 32-bit editions https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 32-bit editions
https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 64-bit editions https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 64-bit editions
https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 32-bit Systems https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 32-bit Systems
https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 64-bit Systems https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 64-bit Systems
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 64-bit editions https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 64-bit editions
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 32-bit editions https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 32-bit editions
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 32-bit editions https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 32-bit editions
https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 64-bit editions https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 64-bit editions
https://aka.ms/OfficeSecurityReleases
Product Identifier Version Remediation
Microsoft Office LTSC 2024 for 64-bit editions <https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 64-bit editions
<https://aka.ms/OfficeSecurityReleases
Vendor Fix fix
Microsoft Office LTSC 2024 for 32-bit editions <https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2024 for 32-bit editions
<https://aka.ms/OfficeSecurityReleases
Vendor Fix fix
Microsoft Office LTSC 2021 for 32-bit editions <https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 32-bit editions
<https://aka.ms/OfficeSecurityReleases
Vendor Fix fix
Microsoft Office LTSC 2021 for 64-bit editions <https://aka.ms/OfficeSecurityReleases
Microsoft Office LTSC 2021 for 64-bit editions
<https://aka.ms/OfficeSecurityReleases
Vendor Fix fix
Microsoft 365 Apps for Enterprise for 64-bit Systems <https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 64-bit Systems
<https://aka.ms/OfficeSecurityReleases
Vendor Fix fix
Microsoft 365 Apps for Enterprise for 32-bit Systems <https://aka.ms/OfficeSecurityReleases
Microsoft 365 Apps for Enterprise for 32-bit Systems
<https://aka.ms/OfficeSecurityReleases
Vendor Fix fix
Microsoft Office 2019 for 64-bit editions <https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 64-bit editions
<https://aka.ms/OfficeSecurityReleases
Vendor Fix fix
Microsoft Office 2019 for 32-bit editions <https://aka.ms/OfficeSecurityReleases
Microsoft Office 2019 for 32-bit editions
<https://aka.ms/OfficeSecurityReleases
Vendor Fix fix
Threats
Impact Elevation of Privilege
Exploit Status Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Unlikely
Acknowledgments
0ccbbf129444eb66344ccafb92b00df4

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          "text": "Microsoft",
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          "text": "No, the Preview Pane is not an attack vector.",
          "title": "Is the Preview Pane an attack vector for this vulnerability?"
        },
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            "confidentialityImpact": "HIGH",
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            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
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      "title": "Microsoft Office Click-To-Run Elevation of Privilege Vulnerability"
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}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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Detection rules are retrieved from Rulezet.

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