Heap-based buffer overflow in Microsoft Office for macOS and Microsoft Office - CVE-2026-110055

 

Heap-based buffer overflow in Microsoft Office for macOS and Microsoft Office - CVE-2026-110055

Published: November 10, 2026


Vulnerability identifier: #VU164770
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-2026-110055
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 victim's 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 the file to execute arbitrary code.

The Preview Pane is not an attack vector for this vulnerability.


Affected software

Microsoft Office for macOS
Microsoft Office

How to mitigate CVE-2026-110055

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

External References

Related Security Bulletins