Active Directory (AD) is a useful service that helps organizations manage identities and control access to network resources, thus improving corporate cybersecurity. However, when poorly managed, AD can be exploited in a way that hurts an organization’s cybersecurity.
In this article, we briefly define what Active Directory is and list its main services and possible threats. We also explore in detail two proven ways to keep AD safe and sound: an Active Directory audit and privileged access management.
The importance of Active Directory security
Why should you think of Active Directory security?
Active Directory, or AD, is a service that enables administrators to manage permissions and access to network resources. Developed by Microsoft for Windows domain networks, AD is used to allow users and computers access to specific applications and files based on their identity.
AD significantly simplifies user identity and access privilege management for administrators. It also supports redundant components and data replication to ensure resiliency.
Data is stored in AD as objects. Objects can be defined as resources (if they are applications or devices) or as security principals (if they are users or groups of users).
There are five key services that comprise Windows Active Directory, with Active Directory Domain Services (AD DS) being the core:
Since admins use Active Directory for user authentication and authorization, it’s a common target for cyber attacks. Malicious actors, both external and internal, may want to compromise AD because it will help them access user accounts, databases, files, applications, and sensitive data of the target organization.
Here are some of the most common threats to Active Directory:
Default settings. Microsoft provides Windows Active Directory with predefined security settings, which may not be enough for your organization’s needs. Especially since hackers are already familiar with default settings and can use this knowledge when attempting to find and exploit AD security gaps.
Unnecessarily broad access rights. There’s always a risk that system administrators may grant too many privileges to a certain user or group of users. When provided with a higher level of access than needed to perform their jobs, users can be tempted with the opportunity to abuse their access rights with malicious intent. Also, if accounts with extra access privileges get compromised, external attackers will have access to your most valuable resources and data.
Weak passwords for admin accounts. Hackers are likely to use brute force attacks on AD environments, targeting uncomplex passwords for administrative accounts. If those passwords are easy to guess, your organization’s data security is at risk.
Unpatched vulnerabilities on AD servers. Updating software to the latest version along with searching for and patching vulnerabilities is crucial. Otherwise, hackers can find their way into your organization’s IT environment by exploiting unpatched applications and operating systems on AD servers.
How to secure Active Directory?
Since a security compromise of Active Directory can sabotage the integrity of your organization’s IT environment, it’s essential to apply preventive measures and keep an eye on AD protection. To do that, you should regularly perform an Active Directory security audit and establish privileged access management (PAM).
Let’s start with exploring the basics of the Active Directory auditing process and best practices for it.
Active Directory audit: goals and best practices
Active Directory auditing is a set of activities aimed at evaluating the overall security of your AD services. In a nutshell, these processes consist of collecting and analyzing data about AD objects.
Organizations perform such audits to achieve three goals:
Active Directory auditing helps businesses reduce security risks, such as:
- Deeply nested groups that can be challenging to track. AD offers almost unlimited possibilities to create nested groups (groups that are members of other groups). And since nested groups inherit the same access rights as parent groups, there’s a risk of users having unnecessarily extensive permissions.
- Directly assigned permissions that attackers can exploit to gain access to network resources.
- Circular nesting that can cause security issues, such as providing users with too many permissions in applications or causing applications to crash.
An audit can also help you monitor the AD system status, since AD has no alerting tools to update you about issues. For example, during an audit, you can detect degraded replication functions in AD before these functions impact end users. Thus, you can fix issues before anyone notices them.
Last but not least, security auditing of Active Directory can help organizations comply with various IT cybersecurity requirements. The most common standards, laws, and regulations like SOX, the GDPR, and HIPAA oblige organizations to secure sensitive client data and control access to it. AD auditing enables you to track actions — like logging on and off and accessing files and folders — performed by users across your IT infrastructure.
Every organization has its own strategy to secure Active Directory using an AD audit, but the most helpful and commonly used practices are:
Apart from an AD audit, you can also leverage privileged access management (PAM) practices to enhance the security of your Active Directory environment. Let’s take a closer look at what PAM is and what benefits it brings to your AD security.
PAM-based AD protection: benefits and best practices
Privileged access management (PAM) is a comprehensive cybersecurity strategy that aims to control, monitor, audit, and secure all human and non-human privileged identities and activities across an enterprise IT environment.
Establishing robust privileged access management is a must to secure an organization’s data and systems as well as to eliminate various AD-related risks. First of all, this is true because AD itself is managed by privileged accounts. And if these accounts get abused, malicious actors can take advantage of access privileges assigned to them.
System administrators often center PAM solutions around an organization’s Active Directory environment as a way of delegating privileged access from a centralized monitored location.
You might want to use a PAM approach for securing AD, since it can help you to:
- Identify users with elevated permissions
- Detect users with unnecessarily broad access rights
- Manage all privileged accounts from a single point
- Reduce the risks of privilege misuse and data leaks
To get the most out of PAM opportunities for securing your AD environment, let’s explore six helpful practices for establishing proper privileged access management:
1. Keep an inventory of all privileged accounts
To manage privileged accounts efficiently and securely, you need to have full visibility of these accounts. Keeping an inventory of all privileged accounts will help you:
- Know which users can access sensitive data
- Check that privileged access is still necessary for certain users
- Remove elevated access rights once a user doesn’t require them anymore
The exact list of privileged accounts depends on the access control solution or directory service you are using. In Active Directory, default groups of privileged accounts include:
- Enterprise Admins
- Domain Admins
- Schema Admins
However, there can be other groups of privileged accounts within your organization’s infrastructure.
Compiling and managing a list of privileged accounts manually is inefficient, especially for a large organization. Instead, you can use a cybersecurity tool that can automatically discover and display all privileged accounts.
2. Balance privileges with user needs
The less access privileges you grant a user, the lower the risk of their misusing these privileges and causing an insider-related incident. However, it’s often a challenge to minimize privileges without hurting employees’ efficiency.
To overcome this challenge, consider using one of the following techniques or a combination of them:
- Zero trust is a security approach in which access to protected resources is only granted to authenticated and verified users.
- The principle of least privilege states that users should be able to access only the information and resources that are necessary for a legitimate purpose.
- Just-in-time privileged access management (JIT PAM) dictates that only the right users can be provided with privileged access to certain systems and resources, only for a valid reason, and only for the specific time.
With Ekran System, you can minimize privileges conveniently and efficiently, securing access not only to your AD environment but to your organization’s systems and data:
- Approve access manually to determine who can access what and when
- Integrate leading ticketing systems to validate the reasons for privileged access requests
- Configure time-based user access restrictions
- Use one-time passwords to secure temporary access to the most critical endpoints
3. Use multi-factor authentication
Since even strong and secured credentials can be stolen or leaked, it’s always a good idea to enable multi-factor authentication (MFA).
With MFA, you make a user provide something they possess like a key, security token, or smartphone to verify their identity in addition to login and password. Thus, you minimize the risks of unauthorized access to Active Directory.
Ekran System offers you a 2FA solution that uses time-based one-time passwords as the second authentication factor to help you protect your valuable corporate assets. Also, Ekran System’s 2FA is universal and cross-platform, so you can use it for both Linux servers and Windows servers.
4. Manage access controls
Efficiently managing access controls is a sure way to minimize security risks related to excessive access rights. To do that, you can use a role-based access control (RBAC) method or attribute-based access control (ABAC) model.
With the RBAC method, you can easily authorize, restrict, and revoke access for certain groups of users instead of doing it individually for every user. However, you can’t assign permissions to objects and operations, just as you can’t restrict access to certain data within a system.
The ABAC model provides you with an opportunity to describe a business rule of any complexity. For example, you can allow employees to access certain data only during work hours. On the downside, specifying and maintaining such complex policies makes an ABAC system challenging to configure.
5. Monitor the behavior of privileged users
Monitoring of privileged users is a common practice within various organizations, since it helps you know what data users access and what changes they make.
Apart from that, you’d also like to monitor the behavior of privileged users. Thus, you can detect abnormalities in how users act, which can be a sign of malicious activity or a compromised account.
With Ekran System, you can easily establish robust monitoring of privileged user activity and leverage the following benefits:
- Monitor, record, and audit all privileged sessions on chosen endpoints
- Continue recording a session in offline mode if the server connection is lost
- Build a baseline behavior profile for every user or entity in the system
- Detect abnormal actions and instantly notify security officers about them
In addition, you can use Ekran System to automatically generate various user activity reports and analyze overall user activity.
6. Manage shared accounts
While it’s unsafe, organizations tend to use shared accounts for administering their networks or working with third-party services. Thus, different users can log in to the same account under the same credentials to perform certain work-related activities.
But without proper management, shared accounts can become a source of cybersecurity threats, leaving you unable to detect the particular individual behind an incident.
The first thing to do is review all accounts with shared access and check whether shared access is actually required. If not, remove permissions for users who don’t need them. For the remaining shared accounts, it’s best to enable secondary authentication. In this way, you’ll be able to distinguish the actions of particular users performed under a shared account. This can help you investigate a security incident if one occurs.
You can also leverage Ekran System’s capabilities as identity management solution, including secondary authentication to distinguish users of shared and built-in accounts. It will help you gain full visibility over actions performed under generic credentials for root and admin accounts.
Keeping your Active Directory environment protected from possible misuse and attacks is a significant part of every organization’s cybersecurity strategy. Using PAM best practices and regularly conducting an AD audit will help you keep your Active Directory environment secure.
Ekran System offers a wide selection of features to help you efficiently manage user access rights, monitor users’ activity, and detect suspicious actions before they lead to a cybersecurity incident. With Ekran System, you can secure access to your Active Directory environment as well as ensure Linux/Unix and Windows user activity monitoring.
Download a demo of Ekran System or request a trial to see how you can benefit from our privileged access management functionality!