CVE-2021-42321 (Microsoft Exchange) is in the CISA Known Exploited Vulnerabilities catalog since 2021-11-17. Used in ransomware. An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange… See the required fix, due date and advisories.
CVE-2021-42321 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 2021-11-17. An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange and perform remote code execution.
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Wording published by CISA for this catalog entry. It is the baseline action, not a decision about your environment: whether this exposure matters for you depends on where the affected component runs, what it is exposed to and who owns it.
A catalog entry tells you a vulnerability is being exploited somewhere. It does not tell you whether it matters in your estate, who owns the fix, or what evidence an auditor will ask for later. That is the work VulnTrek does: it takes findings from the tools you already run, decides which exposure actually matters, routes it to an owner, keeps remediation human-approved and retains the lineage as evidence.
Sourced from public upstream advisories (CISA KEV, ENISA EUVD, vendor PSIRTs) mirrored daily. Informational only — not a remediation decision, not legal advice, and the absence of a record is not evidence of safety.