Use-after-free in Microsoft Office for macOS and Microsoft Office - CVE-2026-124187
Published: November 11, 2026
Vulnerability identifier: #VU165496
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-2026-124187
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 in the victim user's context.
The vulnerability exists due to use-after-free in Microsoft Office Excel when processing a specially crafted workbook. A remote attacker can send a specially crafted Excel workbook and convince a user to open it and review tracked changes to execute arbitrary code in that user's context.
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-2026-124187
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