CVE-2026-40421 - Vulnerability Details - OpenCVE

External control of file name or path in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact partial

Vendors	Products
Microsoft	365 Apps Office 2019 Office 2021 Office 2024 Word 2016

No data.

No data.

References

Link	Providers
https://www.spirityenterprise.com/managed-detection-response-microsoft
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40421

History

Wed, 13 May 2026 20:15:00 +0000

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

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

Type	Values Removed	Values Added
Description		External control of file name or path in Microsoft Office Word allows an unauthorized attacker to disclose information over a network.
Title		Microsoft Word Information Disclosure Vulnerability
First Time appeared		Microsoft Microsoft 365 Apps Microsoft office 2019 Microsoft office 2021 Microsoft office 2024 Microsoft word 2016
Weaknesses		CWE-73
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:::* cpe:2.3:a:microsoft:word_2016::::::::
Vendors & Products		Microsoft Microsoft 365 Apps Microsoft office 2019 Microsoft office 2021 Microsoft office 2024 Microsoft word 2016
References		https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40421
Metrics		cvssV3_1 `{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C'}`

MITRE

Status: PUBLISHED

Assigner: microsoft

Published: 2026-05-12T16:58:48.710Z

Updated: 2026-05-13T19:32:43.499Z

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

Link: CVE-2026-40421

Vulnrichment

Updated: 2026-05-13T19:32:37.853Z

NVD

Status : Awaiting Analysis

Published: 2026-05-12T18:17:20.320

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

Link: CVE-2026-40421

Redhat

No data.

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