This vulnerability (CVE-2026-68815) is a heap-based buffer overflow in Microsoft Office Excel, part of Microsoft 365 Apps for Enterprise. It enables an unauthorized attacker to execute code locally. The CVSS 3.1 vector indicates the attack requires local access with low complexity and no privileges but user interaction is required. The impact includes high confidentiality, integrity, and availability impacts. Microsoft has published an official fix and manages remediation for this cloud service. The affected version explicitly stated is 16.0.1.

Successful exploitation allows an unauthorized attacker to execute arbitrary code locally, potentially leading to full compromise of the affected system's confidentiality, integrity, and availability. The vulnerability is rated high severity with a CVSS score of 7.8. No known active exploits have been reported.

An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users and administrators should ensure their Microsoft 365 Apps for Enterprise installations are updated to the fixed version as per Microsoft's advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-68815.