Microsoft Active Directory Domain Services Privilege Escalation Vulnerability

HIGH 7.5EXPLOITED (CISA KEV)CVE-2021-42278 · Published 10/11/2021 · updated 19/08/2026

Microsoft Active Directory Domain Services Privilege Escalation Vulnerability. Actively exploited: CISA added this vulnerability to its Known Exploited Vulnerabilities catalog on 11/04/2022. Patch affected systems as an emergency. It is known to be used in ransomware campaigns.

Package	Affected versions	Patched versions
Active Directory Microsoft	Versions not published yet (product named by CISA KEV)

Description

Active Directory Domain Services Elevation of Privilege Vulnerability

References

msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42278 · Patch
portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42278 · Patch
cisa.gov/known-exploited-vulnerabilities-catalog · US Government Resource
CISA KEV · CVE-2021-42278

Running one of these products? Scan your site to see whether it exposes a vulnerable version.

Scan my site free