CVE-2026-42893: Microsoft Outlook

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

Improper neutralization of special elements used in a command ('command injection') in M365 Copilot allows an unauthorized attacker to perform tampering over a network.

Affected products

• Microsoft Outlook: before 5.2617.1 (fixed in 5.2617.1)

Published 2026-05-12. Last modified 2026-06-17.