CVE-2021-34523

CRITICAL9.0

CISA KEV

Published 2021-07-14 · Updated 2026-08-10 · Source secure@microsoft.com

Description

Microsoft Exchange Server Elevation of Privilege Vulnerability

CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N

CISA Known-Exploited Vulnerability

Product: Microsoft — Exchange Server

Name: Microsoft Exchange Server Privilege Escalation Vulnerability

Date added: 2021-11-03 · Due: 2021-11-17

USED IN RANSOMWARE

Required action: Apply updates per vendor instructions.

References

View on NVD

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