Microsoft Security Response Center guidance
Vendor revision: Jul 30, 2026Click to Run Release Notes Install KB5002887.
Vendor-listed releases
- https://aka.ms/OfficeSecurityReleases
- 16.111.26071215
- 16.0.5561.1000
Vulnerability intelligence
CVE-2026-55129 and is rated High severity with a CVSS score of 7.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.
Click to Run Release Notes Install KB5002887.
Vendor-listed releases
Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.
Source: NVD