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CVE-2021-26855

🔥 Known Exploited (CISA KEV)CRITICAL

9.1

CVSS Severity Score

EPSS Score77.9900%

EPSS Percentile90.51th

Published2021-03-03

Last Modified2025-12-18

Data SourcesNVDCISA KEVFIRST.org EPSS

Vulnerability Description

Microsoft Exchange Server Remote Code Execution Vulnerability

Affected Platforms (CPE)

📦

Microsoft

Exchange Server

= 2013= 2016= 2019

References & Advisories

🔗 http://packetstormsecurity.com/files/161846/Microsoft-Exchange-2019-SSRF-Arbitrary-File-Write.html

🔗 http://packetstormsecurity.com/files/161938/Microsoft-Exchange-ProxyLogon-Remote-Code-Execution.html

🔗 http://packetstormsecurity.com/files/162610/Microsoft-Exchange-2019-Unauthenticated-Email-Download.html

🔗 http://packetstormsecurity.com/files/162736/Microsoft-Exchange-ProxyLogon-Collector.html

🔗 https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26855

🔗 http://packetstormsecurity.com/files/161846/Microsoft-Exchange-2019-SSRF-Arbitrary-File-Write.html

🔗 http://packetstormsecurity.com/files/161938/Microsoft-Exchange-ProxyLogon-Remote-Code-Execution.html

🔗 http://packetstormsecurity.com/files/162610/Microsoft-Exchange-2019-Unauthenticated-Email-Download.html

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