Active Directory

Welcome to the Active Directory series.

Modern enterprise environments rely heavily on Active Directory to manage users, computers, permissions, authentication, and access to organizational resources.

For both attackers and defenders, understanding Active Directory is one of the most valuable skills in Windows security.

This series aims to explain Active Directory from the ground up—not just how to use tools, but how the underlying components work together and why they matter.

Rather than focusing solely on attack techniques, we’ll first build a solid understanding of the technology itself. Once those foundations are in place, we’ll explore how misconfigurations and design choices can be abused during real-world engagements.

Who is this series for?

This series is intended for:

Penetration Testers
Red Team Operators
Blue Team Analysts
Detection Engineers
System Administrators
Security Researchers
Students learning enterprise security

Whether your goal is to perform Active Directory assessments or defend enterprise networks, understanding the fundamentals is essential.

What you’ll learn

Topics covered throughout this series include:

Active Directory architecture
Domains
Forests
Trees
Organizational Units (OUs)
Domain Controllers
LDAP
Kerberos
NTLM
Group Policy
DNS integration
Access Control Lists (ACLs)
Delegation
Trust Relationships
Service Accounts
SPNs
Active Directory Certificate Services (AD CS)
Common attack paths
Defensive best practices

Each topic builds on previous concepts, so following the series sequentially is recommended.

Why Active Directory Matters

Active Directory is often the central identity platform within Windows enterprise environments.

A vulnerability or misconfiguration affecting Active Directory can impact an entire organization.

Understanding authentication, authorization, directory services, and permissions helps explain why attacks such as:

Kerberoasting
AS-REP Roasting
DCSync
Resource-Based Constrained Delegation
ACL abuse
Golden Ticket attacks
Silver Ticket attacks

are possible—and, more importantly, how to identify and mitigate them.

Prerequisites

Helpful background knowledge includes:

Basic networking
Windows operating system fundamentals
Command-line experience
Basic cybersecurity concepts

No prior Active Directory experience is required.

Series Roadmap

Topics will generally include:

Active Directory Overview
Domain Controllers
Domains, Trees, and Forests
LDAP
Kerberos Authentication
NTLM Authentication
DNS in Active Directory
Organizational Units
Group Policy
Service Accounts
SPNs
Access Control Lists
Delegation
Trust Relationships
AD CS
Active Directory Attack Paths
Defensive Hardening

Learning Approach

This series focuses on building intuition before introducing attack techniques.

For every concept, we’ll examine:

What problem does this component solve?
How does it work internally?
Where are common misconfigurations?
How can attackers abuse it?
How can defenders detect and prevent abuse?

By understanding the architecture first, offensive techniques become much easier to reason about, and defensive strategies become more meaningful.

Let’s get started.