Executive Decision Brief
Active Directory Certificate Services (ADCS) is frequently overlooked during security assessments, yet misconfigured certificate templates provide attackers with direct, stealthy escalation paths from unprivileged domain users to Domain Admin. This guide provides step-by-step remediation for all known ADCS abuse vectors (ESC1 through ESC14).
Strategic Takeaways for Executive Leadership:
- Audits and remediates certificate templates permitting enrollee-supplied Subject Alternative Names (SANs - ESC1).
- Secures web enrollment endpoints against NTLM relaying attacks (ESC8) via Extended Protection for Authentication (EPA).
- Prevents persistent domain persistence through forged Golden Certificates (PKINIT authentication abuse).
- Provides PowerShell and Certify audit scripts to continuously detect misconfigured certificate templates.
Target Executive Audience:
Misconfigured Certificate Templates Allow Low-Privilege Users to Request Valid Domain Admin Certificates
When an ADCS certificate template is configured with client authentication capabilities and allows enrollees to specify a Subject Alternative Name (SAN), any low-privilege domain user can request a certificate in the name of the Domain Administrator.
The attacker then uses Kerberos PKINIT authentication to exchange the forged certificate for a Domain Admin Ticket-Granting Ticket (TGT), achieving full domain compromise in seconds without triggering standard password monitoring alerts.
| Abuse ID | Root-Cause Misconfiguration | Required Remediation Action |
|---|---|---|
| ESC1 | Template allows enrollee-supplied SAN + Client Auth EKU + Broad enrollment rights | Disable 'Supply in the request'; enforce CA manager approval on high-privilege templates |
| ESC2 / ESC3 | Any Purpose EKU or Certificate Request Agent abuse | Restrict enrollment agent issuance policies and eliminate unconstrained EKUs |
| ESC4 | Misconfigured ACLs on certificate templates allowing low-privilege modification | Audit template write ACLs; remove write permissions for Authenticated Users |
| ESC8 | ADCS Web Enrollment HTTP endpoints allowing unauthenticated NTLM relay | Enforce HTTPS, disable NTLM authentication, and enable Extended Protection for Authentication (EPA) |
Regulatory & Framework Mapping
Exact alignment of technical requirements to Bank Negara Malaysia, NACSA, and international standards.
| Framework & Clause | Mandatory Obligation | nCrypt Solution Capability | Audit Evidence Deliverable |
|---|---|---|---|
| BNM RMiTSection 10.23 | Robust identity authentication and prevention of unauthorized privilege escalation | ADCS Technical Audit & Automated Template Hardening | ADCS Vulnerability Assessment Report & Template Remediation Script Package |
RFP Scoping & Vendor Due Diligence Checklist
Criteria for technical evaluation committees assessing external cybersecurity service providers in Malaysia.
PKI Tooling
Executive & Technical Questions
Why are ADCS vulnerabilities particularly dangerous?
Because certificate-based authentication generates legitimate Kerberos tickets directly from the Domain Controller, leaving no password-guessing or hash-cracking logs in the event viewer.
Disclaimer: This whitepaper is published for strategic decision-support and technical guidance. It does not constitute formal legal counsel. Malaysian enterprises should validate specific statutory interpretations with qualified counsel.
Accreditation Context: nCrypt uses CREST-aligned methodologies and deploys certified practitioners (OSCP, CRTO, CISA, CISSP). NACSA Cybersecurity Service Provider (CSP) license application submitted; ISO/IEC 27001 audit in progress.