Main Vulnerability Database Vulnerabilities #VU138194

Use-after-free in Microsoft Office for macOS and Microsoft Office - CVE-2026-55018

Published: July 17, 2026

Vulnerability identifier: #VU138194

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-2026-55018

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to use-after-free in Microsoft Office when parsing a crafted Office file. A remote attacker can send a specially crafted file to a user and convince them to open it to execute arbitrary code.

User interaction is required, and the Preview Pane is an attack vector.

Affected software

Microsoft Office for macOS
Microsoft Office

How to mitigate CVE-2026-55018

Install security update from vendor's website.

Microsoft Office for macOS - update to 16.111.26071215
Microsoft Office - update to 16.0.5561.1000

External References

Related Security Bulletins