Main Vulnerability Database Vulnerabilities #VU155589

Double free in Office Online Server and Microsoft Office - CVE-2026-97767

Published: October 14, 2026

Vulnerability identifier: #VU155589

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-2026-97767

CWE-ID: CWE-415

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 double free in Microsoft Office Excel when opening a malicious Office file. A remote attacker can send a malicious Office file to a user and convince them to open it to execute arbitrary code.

The Preview Pane is not an attack vector.

Affected software

Office Online Server
Microsoft Office

How to mitigate CVE-2026-97767

Install security update from vendor's website.

Office Online Server - update to 16.0.10417.20228
Microsoft Office - addressed in versions 16.0.14334.20974, 16.0.17932.21056

External References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-97767

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