CVE-2021-26854

—

CVSS 3.1

6.6 medium

EPSS

23%p98

Published

Mar 3, 2021 (Mar 3, 2021)

Modified

Aug 19, 2026

Description

Microsoft Exchange Server Remote Code Execution Vulnerability

Vendors: microsoft
Products: exchange server
Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H

NVD CVE.org GitHub PoCs EPSS (23.0%)

In the news2 stories

Microsoft: Chinese APT Targeted Exchange Servers With Four Zero

The RecordJan 30, 00:00 UTC · Jan 30, 2023Exploit / PoC CVE-2021-26855 CVE-2021-26857 CVE-2021-26858+4 CVEs

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Threat Advisory: HAFNIUM and Microsoft Exchange zero

Cisco TalosMar 4, 15:58 UTC · Mar 4, 2021Advisory in the wildCVE-2021-26855 CVE-2021-26857 CVE-2021-26858+5 CVEs1

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