All CVEs
CVE-2021-27065
HIGH7.8
CISA KEV
Published 2021-03-03 · Updated 2026-08-19 · Source secure@microsoft.com
Description
Microsoft Exchange Server Remote Code Execution Vulnerability
CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE-22CWE-22
CISA Known-Exploited Vulnerability
Product: Microsoft — Exchange Server
Name: Microsoft Exchange Server Remote Code Execution Vulnerability
Date added: 2021-11-03 · Due: 2022-05-03
USED IN RANSOMWARE
Required action: Apply updates per vendor instructions.
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-27065
- http://packetstormsecurity.com/files/161938/Microsoft-Exchange-ProxyLogon-Remote-Code-Execution.html
- http://packetstormsecurity.com/files/162736/Microsoft-Exchange-ProxyLogon-Collector.html
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-27065
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-27065