competition-ad-certificate-abuse

Imported from zhaoxuya520/reverse-skill (CTF-Sandbox-Orchestrator/competition-ad-certificate-abuse/SKILL.md). Install upstream with npx skills add zhaoxuya520/reverse-skill --skill competition-ad-certificate-abuse. Copyright stays with the author.

Competition AD Certificate Abuse

Use this skill only as a downstream specialization after $ctf-sandbox-orchestrator is already active and has established sandbox assumptions, node ownership, and evidence priorities. If that has not happened yet, return to $ctf-sandbox-orchestrator first.

Use this skill when the decisive identity edge is certificate-based and the hard part is proving how a template or CA policy turns into accepted privilege.

Reply in Simplified Chinese unless the user explicitly requests English.

Quick Start

1. Identify the CA, template, enrolling principal, and accepting service before diving into every certificate detail.
2. Separate template enrollability from cert-based authentication or privilege acceptance.
3. Record EKUs, subject or SAN controls, issuance requirements, enrollment rights, and mapping behavior in compact blocks.
4. Tie the issued cert to one accepted path: PKINIT, Schannel, LDAPS, WinRM, or another mapped service.
5. Reproduce the smallest certificate issuance-to-acceptance chain that yields the decisive privilege.

Workflow

1. Map CA And Template Trust

• Record CA configuration, template name, enrollment permissions, manager approval, authorized signatures, EKUs, subject requirements, and SAN behavior.
• Note whether the path depends on alternate subject names, UPN, DNS names, enrollment agent behavior, or template supersedence.
• Keep principal, template, and issuance policy tied together.

2. Prove Cert-To-Privilege Acceptance

• Show how the issued certificate is mapped or accepted: PKINIT, smartcard logon, Schannel auth, service mapping, or explicit certificate mapping.
• Record serial, subject, SAN, EKU, validity, and the exact service or domain edge that accepts it.
• Distinguish certificate issuance from the separate step where privilege is actually granted.

3. Reduce To The Decisive Abuse Chain

• Compress the path to the smallest sequence: enrollment right or misconfig -> issued cert -> accepted mapping -> resulting privilege.
• State clearly whether the weakness lives in template config, CA policy, mapping logic, relay path, or enrollment rights.
• If the task is really about delegation or ticket transformation after PKINIT, switch back to the tighter Kerberos skill.

Read This Reference

• Load references/ad-certificate-abuse.md for the AD CS checklist, template checklist, and evidence packaging.

What To Preserve

• CA names, template names, rights, EKUs, issuance flags, SAN controls, and mapping details
• Issued certificate fields, serials, subjects, SANs, and the accepting service or logon path
• The smallest reproducible enrollment-to-privilege chain