Type Confusion in Microsoft products - CVE-2026-40364
Published: May 13, 2026
Vulnerability identifier: #VU131352
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-40364
CWE-ID: CWE-843
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a type confusion error in Microsoft Word. A remote attacker can pass specially crafted data to the application, trigger a type confusion error and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Affected software
Microsoft 365 Apps for Enterprise
Microsoft Office
Microsoft Word
Microsoft Office LTSC
Microsoft Office
Microsoft Word
Microsoft Office LTSC
How to mitigate CVE-2026-40364
Install updates from vendor's website.
Microsoft Word - update to 16.0.5552.1000