This vulnerability involves an integer overflow or wraparound in Microsoft Office Excel, part of Microsoft 365 Apps for Enterprise, which could enable an unauthorized attacker to execute code locally on the affected system. The CVSS 3.1 base score is 7.8, indicating high severity, with attack vector local, low attack complexity, no privileges required, and user interaction required. Microsoft has published an official fix and manages remediation for this cloud service. No active exploitation has been reported.

Successful exploitation could lead to local code execution by an unauthorized attacker, potentially resulting in full confidentiality, integrity, and availability compromise of the affected system. The vulnerability requires local access and user interaction to be exploited.

An official fix is available from Microsoft. Since this is a cloud-hosted service, Microsoft manages remediation server-side. Users and administrators should apply the official updates as directed in the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55048 to ensure protection.