HIGHCVSS 8.8Actively exploited · CISA KEV since 2021-11-17Vulnerability
CVE-2021-42321
An authenticated attacker could leverage improper validation in cmdlet arguments within Microsoft Exchange and perform remote code execution.
Properties
- Euvd product
- Microsoft Exchange Server 2019 Cumulative Update 11, Microsoft Exchange Server 2016 Cumulative Update 21, Microsoft Exchange Server 2019 Cumulative Update 10, Microsoft Exchange Server 2016 Cumulative Update 22
- Vulnerability name
- Microsoft Exchange Server Remote Code Execution Vulnerability
- First seen
- 2026-08-19T16:27:07+00:00
- Cvss score
- 8.8
- Epss score
- 0.91737
- Last seen
- 2026-10-19T12:00:27+00:00
- Due date
- 2021-12-01
- Euvd assigner
- microsoft
- Retrieved at
- 2026-10-21T01:24:47+00:00
- Exploited euvd since
- 2021-11-17T00:00:00+00:00
- Src batch id
- epss_history-20261020T103617Z-728ddd
- Source url
- https://epss.empiricalsecurity.com/epss_scores-2026-10-19.csv.gz
- Date added
- 2021-11-17
- Euvd base score version
- 3.1
- Score
- 8.8
- Fetched at
- 2026-10-20T10:36:20+00:00
- Euvd vendor
- Microsoft
- Cvss vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- In Signal since
- initial import (Sep 2026)
- Euvd base score
- 8.8
Related Entities (6)
AFFECTS_PRODUCT (4)
DESCRIBES (1)
INVOLVES (1)
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