CVE-2026-100208: Microsoft 365 Apps For Enterprise

High severity, CVSS 7.5. EPSS: 0.3% chance of exploitation in the next 30 days.

Integer overflow or wraparound in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.

Affected products

• Microsoft Microsoft 365 Apps For Enterprise
• Microsoft Microsoft Office Ltsc 2021
• Microsoft Microsoft Office Ltsc 2024

Published 2026-09-25. Last modified 2026-09-29.