CVE-2021-42287
Active Directory Domain Services Elevation of Privilege Vulnerability
- High 7.5
- Exploited: added to CISA KEV 11 Apr 2022
- Used in ransomware campaigns
Description
Active Directory Domain Services Elevation of Privilege Vulnerability
Key facts
- Published
- 10 Nov 2021
- Last changed
- 19 Aug 2026
- Assigned by
- microsoft
- KEV added
- 11 Apr 2022
- KEV fix due
- 2 May 2022
- Used in ransomware
- Yes, according to CISA
- EPSS
- 77.17% likely to be exploited in the next 30 days, higher than 99.56% of CVEs (scores for 15 Nov 2026)
- SSVC (CISA)
- Exploitation: active; Automatable: no; Technical impact: total
Severity scores
Each score is shown as its source gave it. They are not averaged or merged.
- 7.5CVSS 3.1, Highfrom the CNA (microsoft)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
What to do
- Apply updates per vendor instructions.CISA KEV required action
Historical context and remediation
This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.
No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.
Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Windows Server 2008 R2 Service Pack 1 |
|
| Microsoft | Windows Server 2008 R2 Service Pack 1 (Server Core installation) |
|
| Microsoft | Windows Server 2008 Service Pack 2 |
|
| Microsoft | Windows Server 2008 Service Pack 2 (Server Core installation) |
|
| Microsoft | Windows Server 2012 |
|
| Microsoft | Windows Server 2012 (Server Core installation) |
|
| Microsoft | Windows Server 2012 R2 |
|
| Microsoft | Windows Server 2012 R2 (Server Core installation) |
|
| Microsoft | Windows Server 2016 |
|
| Microsoft | Windows Server 2016 (Server Core installation) |
|
| Microsoft | Windows Server 2019 |
|
| Microsoft | Windows Server 2019 (Server Core installation) |
|
| Microsoft | Windows Server 2022 |
|
| Microsoft | Windows Server version 2004 |
|
| Microsoft | Windows Server version 20H2 |
|
Timeline
- 10 Nov 2021 Published
- 11 Apr 2022 Added to the CISA KEV catalogue