CVE-2021-26427: Microsoft Exchange Server

Critical severity, CVSS 9.0. EPSS: 0.9% chance of exploitation in the next 30 days.

Microsoft Exchange Server Remote Code Execution Vulnerability

Affected products

• Microsoft Exchange Server: version 2013 only; version 2016 only; version 2019 only

Published 2021-10-13. Last modified 2026-06-17.