This vulnerability, identified as CVE-2026-44823, is a numeric truncation error (CWE-197) in Microsoft Office Excel, part of Microsoft 365 Apps for Enterprise. It enables an unauthorized attacker to execute code locally on the affected system. The CVSS v3.1 base score is 7.8, indicating high severity, with attack vector local, low attack complexity, no privileges required, user interaction required, and high impact on confidentiality, integrity, and availability. The vulnerability affects version 16.0.1 of the product. Microsoft has issued an official fix and manages remediation for this cloud service. No known exploits are reported in the wild.

Successful exploitation allows an unauthorized attacker to execute code locally, potentially leading to full compromise of confidentiality, integrity, and availability of the affected system. The high CVSS score reflects significant impact if exploited.

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 are updated according to Microsoft's guidance at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-44823.