Red Forest Active Directory: Active Directory Management with the “Red Forest”

Red Forest Active Directory? Almost all organizations rely on Active Directory as the primary authentication mechanism on their network. As a result, Active Directory is also the most popular target for attacks. Microsoft’s Active Directory Red Forest design, aka Enhanced Security Administrative Environment (ESAE), is intended to provide an additional level of security.

Active Directory Management with the “Red Forest”

A series of events and data breaches in recent years have brought certain categories of vulnerabilities to light. Perimeter security alone is no longer sufficient to protect our highly dynamic, connected, and mobile enterprises. Additional drivers such as “insider threat” programs are increasingly revealing the need to protect identities. 99 percent of all organizations rely on Active Directory as the primary authentication mechanism. This makes Active Directory the most popular target for attacks.

AD compromise

The stale NTLM hashes generated by Active Directory are one of the main targets of attackers. Here is a brief summary of how such a “pass-the-hash” attack can look like:

The user’s workstation is compromised – often through phishing attacks.
A malicious actor gains administrator privileges for the user’s workstation and causes a problem there that only a person with higher privileges can fix.
The administrator logs on to the workstation to fix the problem. In the process, the administrator’s hash remains in memory.
The attacker then runs software to extract the hash, and then makes network connections from the workstation to resources, data stores, databases, etc. as a privileged user.

Protecting privileged accounts applies to Active Directory as it does to any other system. Accounts, Passwords, credentials are primary targets regardless of whether the system is protected or what security measures have already been implemented. An additional level of security is supposed to be provided by Microsoft’s “Enhanced Security Administrative Environment (ESAE)” … aka “Red Forest” AD architecture.

It is important to note that it is now the forest, not the domain, that is the security boundary. In this ESAE design, the user and resource/application forests trust authentication over Red Forest. in a unidirectional trust relationship.

Management Is Distributed Across Different Tiers:

• Tier 0: Accounts and groups reside in Red Forest and have control over enterprise identities. A Tier 0 account should use a Privileged Access Workstation (PAW) that resides in and is managed through the Red Forest. This account should never interactively log into a system outside of the Red Forest.
• Tier 1: These accounts should reside in the resource or application forest and only interactively log into systems in that forest. They are used when managing cloud services or enterprise applications and operating systems in this forest. Administrators in this tier should use a Privileged Access Workstation (PAW) in the resource forest.
• Tier 2: These administrator accounts are used to control workstations and other devices in the users’ forest.

This segmented management allows potential compromise to be contained. For example, if a Tier 2 administrator account is compromised, access to assets in the user forest is limited. However, when moving between these tiers and accounts, the protections and policies must be much more restrictive when using these accounts.

The following restrictions regarding interactive login should be noted. The biggest problem with interactive login is that it leaves remnants of the authentication process in memory or in the registry. If an administrator wants to access a resource of a level other than his or her own, he or she must use the “network login” type to log in. Interactive logon must be strictly controlled by group policies or local policies.

What does ESAE do?

ESAE (aka “Red Forest”) provides risk management for AD and the Windows operating systems in the enterprise up to a certain point. If a system is compromised and the attack is discovered, the entire infrastructure does not have to be immediately rebuilt. The design effectively creates “expendable” administrator accounts or connections that can be disconnected to limit the scope of a data breach. One can then remove the affected forest from the trust.

How can multifactor authentication help?

MFA offers administrators a not inconsiderable advantage, especially in the context of phishing attacks. In fact, vulnerabilities that ESAE is designed to prevent are pass-the-hash attacks.

Passwords themselves are not part of this attack. When a user or administrator interactively authenticates with a username/password or via MFA, a hash is generated, and this is the real target.

The Challenge

There are different challenges associated with implementing an ESAE design, which is also related to the size of the organization. Extremely large companies employ numerous administrators at all levels (or tiers). In this case, the complete administration must be handled very strictly. Any exception or “ad-hoc” permission granted can create vulnerabilities that jeopardize the entire security concept. In medium-sized and smaller companies, it is quite common for administrators to perform tasks on many different tiers. In this case, they need separate accounts on these tiers.

It is advisable to subdivide the administration, although it can prove difficult to separate the areas. Again, discrepancies or merging of permissions puts the entire organization at risk. However, effective controls can be put in place without having to implement the complexity of the Enhanced Security Admin Environment design. The first step is to take a basic inventory. It includes all processes within the administrative environment, the tasks to be performed, and the permissions needed to perform them.

A best practice for increased security for administrative accounts is to continuously change passwords through a solution such as One identity Safeguard, making the hashes unusable. When accounts are included in this solution for administration, this allows for controlled access and automatic changing of passwords after each use.

Any remaining traces of the last login are thus rendered unusable. In addition, administrator sessions can be protected via the solution’s session management. In this scenario, the administrator simply requests a session on the end system without having to know or protect a password or other credential.

These solutions are designed so that organizations do not have to go through the hassle associated with ESAE. Potentially vulnerable administrator accounts are managed through this solution, eliminating the pass-the-hash vulnerability. Session management can be used to replay all administrator sessions and audit the activities associated with them.

During the session, the Privileged Analytics feature can be used to evaluate administrative activities and detect deviations from normal behavior. For example, based on location, systems accessed, commands executed, and times of the day. Similarly, deviating patterns in typing behavior and mouse movement can be detected. If an anomaly is detected by the system, countermeasures can be taken, such as sending a notification to the IT security department, having the session paused or terminated.

One Identity Active Roles controls and automates the assignment of AD permissions. Administration only takes place within this solution, all changes are then implemented via a service account in Active Directory. This allows the necessary administrative permissions to be granted at a far more granular level than is possible with native tools. The administration is delegated exactly as needed, with no accumulation of permissions or unwanted deviations regardless of OU structure.

Membership in administrative groups should be managed in a rule-based and automated manner. This membership should only exist for the time period actually needed. Tools such as One Identity Active Roles make this possible with the help of approval workflows and via dynamic and temporary assignment of group memberships.

Administrator accounts are added to privileged groups only when authorization is needed to perform a specific task. This group membership is only valid for exactly this period of time. This approach minimizes the attack surface of the directory and thus protects the administrative account.

Whether it is a multinational company or a single forest organization, it is important to understand exactly how the administrative tasks are performed, what permissions are required to do so, who was granted access, and who had the necessary permissions. The ESAE architecture, while complex, provides significantly more security and resilience than a single AD forest with native permissions and roles.

One Identity solutions are designed to simplify and standardize the management of complex environments in particular. They can be specifically focused on an Active Directory environment, as in the case of ESAE, or cover all systems, devices, and applications.

What is Red Forest Active Directory?

The term “Red Forest” in the context of Active Directory refers to an enhanced and highly secure tier of a Windows Active Directory (AD) forest. Red Forest is also known as the “Enhanced Security Administrative Environment” (ESAE), and it is designed to protect the most critical assets within an organization’s IT infrastructure. The primary purpose of Red Forest is to safeguard against advanced persistent threats (APTs) and mitigate the risk of unauthorized access to sensitive data and privileged accounts.

It is particularly important in environments where there are elevated security concerns, such as government, military, or critical infrastructure organizations.

Key characteristics and components of a Red Forest:

Isolation: The Red Forest is physically and logically isolated from the standard Active Directory environment. It operates as a separate forest, distinct from the organization’s primary or “Green Forest.”

• Security Zones: Red Forest typically consists of three security zones:
• Red Administrative Forest (RAF): This zone contains the most sensitive accounts and security groups, such as enterprise admins, domain admins, and other high-privileged accounts.
• Red Resource Forest (RRF): It hosts administrative accounts that are used to manage the RAF, along with security and auditing components.
• External Network: This is a secure boundary to control traffic and provide protection from external threats.

Credential Isolation: Administrative accounts are kept separate in the Red Forest, reducing the risk of compromise of highly privileged credentials in the Green Forest.

Tiered Administration: The administrative tasks are divided between the Green and Red Forests. Routine, day-to-day activities are handled in the Green Forest, while high-privileged actions are managed in the Red Forest.

Enhanced Security: The Red Forest is subjected to more stringent security controls, including stricter access policies, multi-factor authentication, extensive auditing, and continuous monitoring.

Privilege Access Workstations (PAWs): Administrators use dedicated and secure PAWs for accessing the Red Forest, reducing the risk of credential theft.

Firewall and Network Segmentation: Network communication between the Red and Green Forests is tightly controlled and monitored, and only necessary traffic is allowed.

The Red Forest design is based on the principle of “admin tiers,” where administrative tasks are compartmentalized, and elevated privileges are granted only when necessary. This approach minimizes the attack surface and reduces the risk of unauthorized access to critical systems.

Frequently Asked Questions about “Red Forest Active Directory”

What is the purpose of the Red Forest in Active Directory?

The Red Forest, or Enhanced Security Administrative Environment, is designed to provide an isolated and highly secure tier in Active Directory to protect the most critical assets and privileged accounts within an organization. Its purpose is to safeguard against advanced threats and minimize the risk of unauthorized access to sensitive data and privileged credentials.

How does the Red Forest improve security in Active Directory?

The Red Forest improves security by physically and logically isolating sensitive administrative accounts from the primary Active Directory environment. It enforces strict access controls, multi-factor authentication, and extensive auditing to reduce the risk of unauthorized access and credential compromise.

Is implementing a Red Forest a complex process?

Yes, implementing a Red Forest is a complex and resource-intensive process. It involves creating a separate Active Directory forest, setting up security zones, configuring firewall rules, and creating a tiered administrative model. It also requires careful planning and expertise in Active Directory and security best practices.

What are Privileged Access Workstations (PAWs), and how do they relate to the Red Forest?

Privileged Access Workstations (PAWs) are dedicated, secure workstations used by administrators for high-privileged tasks. They are an integral part of the Red Forest security model and are used to access the Red Forest. PAWs reduce the risk of credential theft and protect sensitive administrative accounts.

In which types of organizations is the Red Forest typically implemented?

The Red Forest is typically implemented in organizations with elevated security concerns, such as government agencies, military organizations, critical infrastructure providers, or any entity that handles highly sensitive and valuable data. It is part of Microsoft’s recommended security best practices for securing high-value assets.