CVE-2026-40421

Files or directories accessible to external parties in Microsoft Office Word allows an unauthorized attacker to disclose information locally.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40421	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:365_apps:-::::enterprise::x64:*
	cpe:2.3:a:microsoft:365_apps:-::::enterprise::x86:*
	cpe:2.3:a:microsoft:office:2019::::::x64:
	cpe:2.3:a:microsoft:office:2019::::::x86:
	cpe:2.3:a:microsoft:office:2024::::ltsc::x64:*
	cpe:2.3:a:microsoft:office:2024::::ltsc::x86:*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021::::::x64:
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021::::::x86:
	cpe:2.3:a:microsoft:word:2016::::::x64:
	cpe:2.3:a:microsoft:word:2016::::::x86:

History

No history.

Information

Published : 2026-05-12 18:17

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40421

Mitre link : CVE-2026-40421

CVE.ORG link : CVE-2026-40421

JSON object : View

Products Affected

microsoft

office_long_term_servicing_channel
office
365_apps
word

CWE

CWE-73

External Control of File Name or Path

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