CVE-2026-88109

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

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88109	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_2021:-::::ltsc:-:x64:
	cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x86:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x64:
	cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x86:

History

15 Oct 2026, 17:32

Type	Values Removed	Values Added
First Time		Microsoft office 2024 Microsoft Microsoft 365 Apps Microsoft office 2021
CPE		cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x64: cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x86: cpe:2.3:a:microsoft:365_apps:-::::enterprise::x86:* cpe:2.3:a:microsoft:office_2024:-::::ltsc:-:x86: cpe:2.3:a:microsoft:365_apps:-::::enterprise::x64:* cpe:2.3:a:microsoft:office_2021:-::::ltsc:-:x64:
References	~~() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88109 -~~	() https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-88109 - Vendor Advisory

13 Oct 2026, 19:21

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 19:21

Updated : 2026-10-15 17:32

NVD link : CVE-2026-88109

Mitre link : CVE-2026-88109

CVE.ORG link : CVE-2026-88109

JSON object : View

Products Affected

microsoft

office_2024
office_2021
365_apps

CWE

CWE-416

Use After Free

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