Active Directory remains the authentication backbone for over 90% of Fortune 1000 companies. As enterprises adopt hybrid and cloud infrastructures, AD is growing in importance and complexity. All applications, users, and devices trace back to AD for authentication and authorization, making it their ultimate target. For attackers, this represents the holy grail. Compromising Active Directory gives you access to your entire network.
Why attackers target Active Directory
AD acts as the gatekeeper for everything within the enterprise. So when an attacker compromises AD, they gain privileged access that allows them to create accounts, change permissions, disable security controls, and move laterally without triggering most alerts.
The 2024 Change Healthcare breach showed what happens when AD is compromised. In this attack, hackers exploited a server lacking multi-factor authentication and migrated to AD to escalate privileges and perform a very costly cyber attack. Patient care came to a screeching halt. Health records exposed. The organization paid a multi-million dollar ransom.
If an attacker gains control of AD, they control the entire network. Additionally, these attacks look like legitimate AD operations and are often difficult to detect with standard security tools.
Common attack techniques
Golden ticket attacks generate forged authentication tickets that grant full domain access for months. DCSync attacks exploit replication permissions to extract password hashes directly from domain controllers. Kerberoasting gains high privileges by targeting service accounts with weak passwords.
How hybrid environments expand the attack surface
Organizations running hybrid Active Directory face challenges that didn’t exist five years ago. Your identity infrastructure now spans on-premises domain controllers, Azure AD Connect sync, cloud identity services, and multiple authentication protocols.
Attackers exploit this complexity and exploit synchronization mechanisms to pivot between environments. Compromise of OAuth tokens in cloud services provides backdoor access to on-premises resources. Additionally, legacy protocols such as NTLM remain enabled for backward compatibility, providing intruders with easy relay attack opportunities.
A fragmented security posture further exacerbates the situation. On-premises security teams use different tools than cloud security teams, which can create visibility gaps at the perimeter. While security teams struggle to correlate events across platforms, threat actors operate in these blind spots.
Common vulnerabilities exploited by attackers
Verizon’s data breach investigation report found that 88% of breaches involved compromised credentials. Cybercriminals collect credentials through phishing, malware, brute force, and purchasing compromised databases.
Common vulnerabilities in Active Directory
Weak passwords: Users reuse the same passwords for personal and work accounts, so a single breach can put multiple systems at risk. Standard 8-character complexity rules look secure, but hackers can crack them in seconds. Service account issues: Service accounts often have passwords that never expire or change, and are typically granted excessive permissions that allow lateral movement if their security is compromised. Cached credentials: Workstations store administrative credentials in memory, allowing attackers to extract them using standard tools. Poor visibility: Teams lack insight into who is using privileged accounts, what level of access they have, and when they are using them. Stale access: Former employees retain privileged access long after they leave the company. This is because no one audits and removes access, leading to a buildup of old accounts that attackers can exploit.
And the hits keep coming. In April 2025, another critical AD flaw occurred that allowed privilege escalation from low-level access to system-level control. Although Microsoft has released patches, many organizations struggle to quickly test and deploy updates to all domain controllers.
A modern approach to hardening Active Directory
Defending AD requires a multi-layered security approach that addresses credential theft, privilege management, and continuous monitoring.
A strong password policy is your first line of defense
Effective password policies play a critical role in protecting your environment. Blocking passwords from appearing in a compromised database prevents your staff from using credentials the hacker already has. Continuous scanning detects not only when a password is reset, but also when a user’s password is compromised through a new breach. Dynamic feedback also shows users in real time whether their passwords are strong or not, guiding them toward secure passwords they can actually remember.
Privileged access management reduces attack surface
Implementing privileged access management can help minimize risk by restricting when and how administrative privileges are used. Start by separating administrator accounts from standard user accounts and ensuring that compromised user credentials cannot provide administrative access. Enforce just-in-time access, granting elevated privileges only when needed and then automatically revoking them. Route all administrative tasks through privileged access workstations to prevent credential theft from regular endpoints.
Zero Trust principles apply to Active Directory
A zero trust approach strengthens Active Directory security by validating all access attempts rather than assuming trust within the network. Enforce conditional access policies that go beyond usernames and passwords to evaluate a user’s location, device state, and behavioral patterns before granting access. Require multi-factor authentication for all privileged accounts to thwart malicious attackers who steal credentials.
Catch attacks in progress with continuous monitoring
Deploy tools to track all important changes in AD, such as group membership changes, permission grants, policy updates, and unusual replication activity between domain controllers. Then configure alerts for suspicious patterns, such as multiple authentication failures from the same account or administrative actions that occur at 3 a.m. when the administrator is asleep. Continuous monitoring provides the visibility needed to detect and stop attacks before they escalate.
Patch management is a must for domain controllers
Strong patch management practices are essential to maintaining secure domain controllers. Deploying security updates that close privilege escalation paths within days instead of weeks, attackers actively scan unpatched systems.
Active Directory security is a continuous process
Active Directory security is not a one-and-done project. Hackers constantly improve technology, new vulnerabilities emerge, and infrastructure changes. This means that security also requires constant attention and continuous improvement.
Passwords remain the most common attack vector and fixing them is a top priority. For the highest level of protection, invest in a solution that continuously monitors and blocks compromised credentials in real time. For example, tools like Specops Password Policy integrate directly with Active Directory to block compromised credentials before they become a problem.
Specops Password Policy continuously blocks over 4 billion compromised passwords and prevents users from creating credentials that an attacker already has. Daily scans detect compromised passwords in real-time, without waiting for the next password change cycle. Additionally, as users create new passwords, dynamic feedback guides them to powerful options that they actually remember, reducing support calls and improving security. Schedule a live demo of Specops Password Policy today.
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