Heap-based buffer overflow in Microsoft Office for macOS and Microsoft Office - CVE-2026-111295
Published: November 11, 2026
Vulnerability identifier: #VU164793
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-2026-111295
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 with the victim user's permissions.
The vulnerability exists due to a heap-based buffer overflow in Microsoft Office Word when saving documents in Word 97-2003 format. A remote attacker can provide a specially crafted Word document and convince a user to open it and save it in that format to execute arbitrary code with the user's permissions.
The Preview Pane is not an attack vector.
Affected software
Microsoft Office for macOS
Microsoft Office
Microsoft Office
How to mitigate CVE-2026-111295
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