CVE-2021-42321🔥 Known Exploited (CISA KEV)HIGH8.8CVSS Severity ScoreEPSS Score57.5490%EPSS Percentile95.29thPublished2021-11-10Last Modified2025-10-30Data SourcesNVDCISA KEVFIRST.org EPSSVulnerability DescriptionMicrosoft Exchange Server Remote Code Execution VulnerabilityAffected Platforms (CPE)📦MicrosoftExchange Server= 2016= 2019References & Advisories🔗 http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html🔗 http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html🔗 https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321🔗 http://packetstormsecurity.com/files/166153/Microsoft-Exchange-Server-Remote-Code-Execution.html🔗 http://packetstormsecurity.com/files/168131/Microsoft-Exchange-Server-ChainedSerializationBinder-Remote-Code-Execution.html🔗 https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42321🔗 https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-42321