Out-of-bounds read in Microsoft products - CVE-2026-81390
Published: September 9, 2026
Vulnerability identifier: #VU148283
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-2026-81390
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to disclose sensitive information.
The vulnerability exists due to an out-of-bounds read in Microsoft Office Excel when processing crafted content. A remote attacker can cause Microsoft Office Excel to process crafted content to disclose sensitive information.
The Preview Pane is not an attack vector.
Affected software
Microsoft Excel
Microsoft 365 Apps for Enterprise
Microsoft Office
Office Online Server
Microsoft 365 Apps for Enterprise
Microsoft Office
Office Online Server
How to mitigate CVE-2026-81390
Install security update from vendor's website.
Microsoft Excel - update to 16.0.5569.1003
Microsoft 365 Apps for Enterprise - update to 16.0.20326.20138
Microsoft Office - addressed in versions 16.0.5569.1003, 16.0.10417.20207, 16.0.14334.20906, 16.0.17932.20976
Office Online Server - update to 16.0.10417.20207
Microsoft 365 Apps for Enterprise - update to 16.0.20326.20138
Microsoft Office - addressed in versions 16.0.5569.1003, 16.0.10417.20207, 16.0.14334.20906, 16.0.17932.20976
Office Online Server - update to 16.0.10417.20207