Buffer over-read in Microsoft Office for macOS and Microsoft Office - CVE-2026-124183
Published: November 11, 2026
Vulnerability identifier: #VU165494
CSH Severity: Medium
CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-124183
CWE-ID: CWE-126
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose potentially sensitive information from heap memory.
The vulnerability exists due to a buffer over-read in Microsoft Office Excel when processing a malicious Office file. A remote attacker can send a specially crafted Office file to a user and convince them to open it to potentially read small portions of heap memory.
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-2026-124183
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