Exposure of Sensitive System Information to an Unauthorized Control Sphere in Microsoft products - CVE-2026-81387
Published: September 9, 2026
Vulnerability identifier: #VU148280
CSH Severity: Low
CVSS v4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-81387
CWE-ID: CWE-497
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 exposure of sensitive system information to an unauthorized control sphere in Microsoft Office Excel when used locally. A remote attacker can exploit the vulnerability locally to disclose sensitive information.
User interaction is required. Disclosure is limited to memory-related information, specifically a heap address returned by the affected service. The Preview Pane is not an attack vector.
Affected software
Microsoft Excel
Microsoft 365 Apps for Enterprise
Microsoft Office
Microsoft 365 Apps for Enterprise
Microsoft Office
How to mitigate CVE-2026-81387
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
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