The Modern Internal Pentest: Active Directory Exploitation Methodology

You have finally bypassed the external perimeter. You drop a payload, catch a shell, and suddenly find yourself staring at an internal Windows environment. The network is vast, the Active Directory (AD) infrastructure is sprawling, and the Domain Controller sits at the center of it all.

What happens next separates the script kiddies from the professionals. Firing off massive, noisy vulnerability scanners is a guaranteed way to get caught by a competent Security Operations Center (SOC). To effectively assess an AD environment, you need a methodical, stealthy, and structured approach.

This guide outlines the standard operating methodology for an authorized internal Active Directory penetration test.

As always, this methodology is framed strictly around authorized testing and bug bounty programs. Do not run these tools on networks you do not own or have explicit, written permission to test.

The Goal & Scope Rules

The primary objective of an internal pentest isn't just "get Domain Admin." It is to demonstrate the business impact of a compromise. Can an attacker access the CFO's emails? Can they dump the customer database? Domain Admin is simply a vehicle to achieve those goals.

Before starting, establish strict scope rules:

• Are there fragile legacy systems that should not be scanned?
• Is account lock-out testing permitted, or strictly forbidden?
• What are the "crown jewels" the business actually cares about protecting?

The Workflow Stage by Stage

Stage 1: Initial Network Poisoning (The Quiet Phase)

Before authenticating to the domain, you can often grab credentials simply by listening to the network. Windows machines are notoriously chatty, frequently broadcasting LLMNR and NBT-NS requests when they cannot resolve a hostname via DNS.

By poisoning these requests, you can trick machines into sending you NTLMv2 hashes.

Tools to use: Responder