The average cost of a data breach now exceeds US$4 million. Robust, continuous Active Directory monitoring can help you reduce the risk of suffering a breach in the first place and reduce the impact of incidents that do occur.
The reason is simple: Active Directory is a key target of attackers because it is the primary authentication and authorization service for over 90 percent of the world’s enterprises. By taking over AD accounts, adversaries gain access to your organization’s vital systems and data, and by abusing AD functionality, they can elevate their privileges and even gain total control of your IT ecosystem. That includes cloud resources, since in most hybrid environments, AD identities are synched to Entra ID (formerly Azure AD).
With effective Active Directory monitoring, you can promptly identify suspicious changes and other activity, so you can immediately take steps to thwart an attack. In particular, AD monitoring looks for indicators of exposure (IOEs), which are clues that a vulnerability exists and could be exploited by attackers. It also looks for indicators of compromise (IOCs), which are signs that a breach has already occurred or is in progress.
Data breaches are not the only risk that organizations need to be concerned about. Non-malicious events like errors by IT admins, power outages and equipment failures can also lead to IT system disruptions or downtime that affect business processes. The cost of such IT system outages — even without a data breach — can exceed $5 million per hour.
Accordingly, organizations need to focus not just on cybersecurity but on cyber resilience: keeping the IT environment up and running as much as possible, and getting it back up and running quickly when a disruption does occur. Active Directory monitoring is essential for cyber resilience because Active Directory is vital for users to do their jobs and for vital processes to run. Simply put, if your Active Directory is down, your business is dead in the water, and costs will quickly begin to mount.
Active Directory delivers a set of services, including Active Directory Domain Services (AD DS), which runs on special servers called domain controllers (DCs). Active Directory services are subject to the same performance issues as any other application, so IT pros need to keep a close eye on Active Directory health and performance through continuous Active Directory monitoring.
Regulations like GDPR, HIPAA, PCI DSS, SOX, FISMA and GLBA differ in the types of data they protect, but they all share a core fundamental goal: controlling who can access regulated data and what they can do with it.
In a Microsoft environment, Active Directory is the core identity repository and provider of authentication and authorization services, making it the gatekeeper for access to regulated data. Robust Active Directory monitoring helps you ensure that only the right people are accessing regulated data. As a result, you can achieve, maintain and prove compliance with a wide range of legislative mandates and industry standards, and avoid steep fines and increased oversight.
Customers today have choices about where they do business. If your IT systems are not available when they’re needed or your organization experiences a security breach that lands it in the headlines, customers will tend to bolt.
Active Directory monitoring helps you stand out from the competition by enabling you to maintain strong cybersecurity and keep your services up and running. This improved cyber resilience can reduce customer churn and is quite attractive to new clients as well.
Active Directory monitoring is essential for a wide range of critical goals, including the following:
A comprehensive Active Directory monitoring strategy should address all of the following elements:
Domain controllers (DCs) are special servers that run the Windows Server operating system and provide Active Directory services. In particular, be sure your Active Directory monitoring plan covers the following:
Identity and access management (IAM) is vital to ensuring security, compliance, productivity and cyber resilience. Key areas of concern for any Active Directory monitoring strategy include:
Group Policy is an exceeding powerful feature of Active Directory. It has literally thousands of settings that enable IT pros to control deploy software, enforce password policies, block use of less-secure Active Directory authentication protocols and much, much more.
Any improper modification to a GPO — whether it’s deliberate or accidental — can disrupt critical services and block legitimate user access to resources, hurting business operations. For example, a single change could give adversaries unlimited attempts to guess account passwords, enable unidentified users to connect to a network share that stores regulated data, or permit the use of USB devices that could unleash ransomware. Therefore, every Active Directory monitoring strategy needs to pay careful attention to Group Policy.
Microsoft offers two types of audit policy settings for monitoring Active Directory users and activity. (Note that Microsoft advises not using both of these options together, since doing so can cause “unexpected results” in audit reporting).
The two types of settings are:
For more comprehensive and effective auditing of user activity, many organizations invest in a third-party AD monitoring solution.
Microsoft provides several Active Directory monitoring tools, including Microsoft System Center Operations Manager (SCOM), Windows PowerShell, Active Directory Users and Computers (ADUC), and the Active Directory Schema snap-ins for Microsoft Management Console (MMC).
However, the functionality of native tools is limited; it’s awkward at best to keep switching between tools; and tasks are often manual, time-consuming and error-prone. Additional important include the following:
To address these limitations, some organizations implement a security information and event management (SIEM) system. However, many SIEM tools rely on the native system event logs, which do not provide a complete picture of what is happening in Active Directory — especially since attackers actively look for ways to circumvent logging in order to avoid detection.
Accordingly, for more comprehensive, reliable and accurate AD monitoring, organizations often invest in third-party Active Directory security solutions that do not rely solely on Windows event logs and that provide a broad suite of valuable functionality.
For effective Active Directory monitoring, follow these best practices:
AD monitoring is part of a broader Active Directory management strategy, which requires a solid foundation. Take a hard look at your Active Directory domains, organizational units (OUs) and schema, and consider how you can make it more manageable and structured. Develop and follow standardized naming practices, and clean up your Active Directory objects, including stale user accounts and Group Policy sprawl. These steps will dramatically simplify management while improving security and compliance.
In addition, it’s invaluable to be able to prevent changes to your most important AD objects, including powerful administrative security groups and crucial GPOs.
Focus your Active Directory monitoring by clearly understanding your Tier 0 assets. In particular, map out the attack paths that could enable an attacker who compromises an ordinary user account to gain control of your domain in a handful of steps. Mitigate the choke points that attack paths share to limit risk, and closely monitor activity around all remaining Tier 0 assets.
An IT environment is a dynamic place; no matter how perfectly you plan your OUs and schemas, you can’t simply set up your Active Directory and forget it. Users, computers, printers and other Active Directory objects come and go, so you’ll need procedures for provisioning and deprovisioning, which should be automated as much as possible through approval-based workflows. You should also regularly identify inactive user and computer accounts so you can clean them up before they can be misused.
More broadly, you also need to monitor the health of your domain controllers and the replication of data between them in real time. Otherwise, users might very well experience problems logging in or accessing the resources they need to do their jobs.
Configuring advanced audit policy enables you to granularly determine what events to collect, which reduces noise. Be sure to establish a reasonable security log size and a flexible retention policy to prevent information loss and overwrites.
Improve your ability to spot attacks and conduct forensic analysis by collecting not just native logs but other critical audit information that is not logged there. Choose an AD monitoring solution that can consolidate and normalize the data to provide contextual information about activity across the IT ecosystem and give you insight into all stages of an incident, from logon to logoff. Ideally, you want a 360-degree view of all related activities across users and resources.
Group Policy is an incredibly powerful and useful tool. Unfortunately, native tools don’t make it easy to keep Group Policy under control, and adversaries are eager to misuse GPOs to further their attacks. Therefore, it’s wise to invest in an Active Directory security tool that provides effective Group Policy management capabilities.
Active Directory monitoring in and of itself isn’t useful — you need to be able to make sense of the immense volume of data collected and respond quickly to potential threats to security, performance or availability. Therefore, you need powerful analytics, advanced alerting, and comprehensive and customizable reporting.