CVE-2021-42321

Summary

CVECVE-2021-42321
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-11-10 01:19:00 UTC
Updated2023-12-28 16:16:00 UTC
DescriptionMicrosoft Exchange Server Remote Code Execution Vulnerability

Risk And Classification

EPSS: 0.903880000 probability, percentile 0.997900000 (date 2026-07-22)

CISA KEV: Listed on 2021-11-17; due 2021-12-01; ransomware use Known

Problem Types: NVD-CWE-Other

CISA Known Exploited Vulnerability

VendorMicrosoft
ProductExchange
NameMicrosoft Exchange Server Remote Code Execution Vulnerability
Required ActionApply updates per vendor instructions.
Noteshttps://nvd.nist.gov/vuln/detail/CVE-2021-42321

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Microsoft Exchange Server 2016 cumulative_update_21 All All
Application Microsoft Exchange Server 2016 cumulative_update_22 All All
Application Microsoft Exchange Server 2019 cumulative_update_10 All All
Application Microsoft Exchange Server 2019 cumulative_update_11 All All

References

ReferenceSourceLinkTags
Microsoft Exchange Server ChainedSerializationBinder Remote Code Execution ≈ Packet Storm MISC packetstormsecurity.com
Security Update Guide - Microsoft Security Response Center MISC portal.msrc.microsoft.com
Microsoft Exchange Server Remote Code Execution ≈ Packet Storm MISC packetstormsecurity.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
CISA Known Exploited Vulnerabilities catalog CISA www.cisa.gov kev

Legacy QID Mappings

  • 50116 Microsoft Exchange Server Remote Code Execution (RCE) Vulnerability - November 2021

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