Heap-based buffer overflow in Microsoft Office for macOS and Microsoft Office - CVE-2026-116923
Published: November 11, 2026
Vulnerability identifier: #VU164988
CSH Severity: High
CVSS v4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-116923
CWE-ID: CWE-122
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the affected system.
The vulnerability exists due to a heap-based buffer overflow in Microsoft Office Word when processing a specially crafted file. A remote attacker can trick a user into opening a specially crafted file to execute arbitrary code on the affected system.
The Preview Pane is not an attack vector for this vulnerability.
Affected software
Microsoft Office for macOS
Microsoft Office
Microsoft Office
How to mitigate CVE-2026-116923
Install security update from vendor's website.
Microsoft Office for macOS - update to 16.115.26110837
Microsoft Office - addressed in versions 16.0.14334.21048, 16.0.17932.21140
Microsoft Office - addressed in versions 16.0.14334.21048, 16.0.17932.21140