An off‑by‑one error in Microsoft Office Word allows an unauthorized attacker to execute arbitrary code when the vulnerable application processes a specially crafted document. The flaw is confined to the Word engine and does not require elevated privileges on the local host; once exploited, code runs under the current user’s identity, potentially granting full control over the compromised system.

The vulnerability affects Microsoft Office 365 for Mac, Microsoft 365 Apps for Enterprise, Microsoft Office LTSC 2021, Microsoft Office LTSC 2024, and their Mac counterparts. Specific affected versions are not listed in the CVE payload, so the affected releases cannot be determined beyond the product families.

The CVSS score of 8.8 indicates high severity. No EPSS score is currently available, and the issue is not listed in the CISA KEV catalog. The likely attack vector is network‑based, with an attacker able to deliver a malicious file or document to a target over the network. Given the high severity and the absence of a known exploit in the wild, the risk remains significant for unpatched systems.