Relaying NTLM for ADCS ESC8
Legal Notice: This skill is for authorized penetration testing, red-team engagements, and educational purposes only. Coercing authentication and relaying credentials against systems you do not own or lack explicit written authorization to test is illegal. Operate strictly within a signed rules-of-engagement; ESC8 coercion can affect production domain controllers.
Overview
ESC8 is one of the Active Directory Certificate Services (AD CS) escalation paths catalogued by SpecterOps in "Certified Pre-Owned." It abuses the AD CS HTTP web-enrollment endpoint (/certsrv/), which by default supports NTLM authentication and, critically, does not enforce HTTPS channel binding or Extended Protection for Authentication (EPA). Because NTLM over HTTP on that endpoint is unprotected, an attacker can coerce a privileged machine account (typically a domain controller) into authenticating to an attacker-controlled host, then relay that NTLM authentication to the CA's web-enrollment page and request a certificate as the coerced machine.
When the relayed victim is a domain controller, the attacker obtains a certificate for the DC's machine …
