CVE-2021-26855

CRITICAL9.1

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:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

CWE-918CWE-918

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

View on NVD

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