CVE-2026-55001: Active Directory Domain Services Elevation of Privilege Vulnerability

Improper certificate validation in Windows Active Directory allows an authorized attacker to elevate privileges locally.

CSIRTS triage

What: Improper certificate validation in Windows Active Directory allows an authorized attacker to elevate privileges locally.
Who is affected: Authorized users of Windows Active Directory are affected.
Urgency: Remediation is urgent due to the high severity and potential for local privilege escalation.
Action: Update Windows Active Directory to the latest version.

AI-assisted analysis generated from the source advisory — verify against the original.

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EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-550010.21% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 12% of all scored CVEs.

CVE	CSIRTS overview	External
CVE-2026-55001	coverage & exploitation status	NVD · CVE.org

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