CVE-2026-40418 - Vulnerability Details - OpenCVE

Use after free in Microsoft Office Click-To-Run allows an authorized attacker to elevate privileges locally.

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact total

Vendors	Products
Microsoft	365 Apps Office 2019 Office 2021 Office 2024

No data.

No data.

References

Link	Providers
https://www.spirityenterprise.com/managed-detection-response-microsoft
https://www.spirityenterprise.com/virtual-ciso
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40418

History

Wed, 13 May 2026 10:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Tue, 12 May 2026 17:30:00 +0000

Type	Values Removed	Values Added
Description		Use after free in Microsoft Office Click-To-Run allows an authorized attacker to elevate privileges locally.
Title		Microsoft Office Click-To-Run Elevation of Privilege Vulnerability
First Time appeared		Microsoft Microsoft 365 Apps Microsoft office 2019 Microsoft office 2021 Microsoft office 2024
Weaknesses		CWE-416
CPEs		cpe:2.3:a:microsoft:365_apps:::::enterprise:::* cpe:2.3:a:microsoft:office_2019:::::::: cpe:2.3:a:microsoft:office_2021:::::long_term_servicing_channel:::* cpe:2.3:a:microsoft:office_2024:::::long_term_servicing_channel:::*
Vendors & Products		Microsoft Microsoft 365 Apps Microsoft office 2019 Microsoft office 2021 Microsoft office 2024
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40418
Metrics		cvssV3_1 `{'score': 7.8, 'vector': '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'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-05-12T16:59:27.930Z

Updated: 2026-05-13T17:59:23.854Z

Reserved: 2026-04-13T00:27:50.799Z

Link: CVE-2026-40418

Vulnrichment

Updated: 2026-05-13T09:58:24.663Z

NVD

Status : Awaiting Analysis

Published: 2026-05-12T18:17:19.940

Modified: 2026-05-13T15:34:52.573

Link: CVE-2026-40418

Redhat

No data.

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