Active Directory (Part 2)

 

Basics

Windows Domains

Window Domain is a collection of networks that are grouped together and share a common directory database. This will help in central management and organization of network resources, such as user accounts, computers, and other devices.

Each domain has its own security policies. They are used to control access to network resources and manage user permissions. The users and computers that are part of a domain are authenticated and authorized to access network resources via the security policies of that domain. 

In AD, domains are hierarchical. A single top-level domain is called the "root domain" at the top of the hierarchy. However, the other domains can be created within the root domain and organized into a tree-like structure. Each domain in the tree is the child of another domain called the "parent domain". This helps in the creation of large and complex network of domains, each with its own security policies and network resources. 

Hence, domains are an essential part of an AD system because they are used to manage and maintain a network's resources. 

Active Directory Overview

Active Directory is installed with a lot of default features that are vulnerable, if not configured correctly or ignored. The central component of any Active Directory Domain Service (AD DS). This services is like a directory that stores the information about all the "object" on the network. AD can support many objects, including users, groups, computers, printers, shared resources, and more.

The most common object type are the users and are considered "security principals." They can be authenticated by the domain and privileges to access certain resources, like files or printers. Security principals are objects that can take actions on resources within the network. Users are of two types:

• People- User accounts often represents individuals in an organization requiring access to the network, such as employees. 

• Services- User accounts can also be created to represent services that run on the network, like IIS or MSSQL. Each service needs a user account to function, but they differ from regular user accounts having necessary privileges only to run specific services. 

A domain consists of several groups that can be used to grant specific privileges to users. Some of the important groups in a domain include: 

• Domain Admins- Users of this group have administrative privileges over the entire domain. By default, they can any computer on the domain, including the DCs.

• Server Operators- Users in this group can administer Domain Controllers. They cannot change any administrative group memberships.

• Backup Operators- Users are allowed to access any file, ignoring their permissions. They are used to perform backups of data on computers.

• Account Operators- In this one, users can create or modify other accounts in the domain.

• Domain Users- Includes all existing user accounts in the domain.

• Domain Computers- Includes all existing computers in the domain. 

• Domain Controllers- Includes all existing DCs on the domain. 

Also, the attacker must understand that Active Directory security groups and Organizational Units (OUs) are two different types of objects with different purposes. 

Security groups manage access to resources on the network. They assign permissions to specific users or computers, allowing them to perform certain actions or access certain resources. They are considered "security principals." It means that they can be authenticated by the domain and can have privileges over resources on the network. 

On the contrary, Organizational Units organize and manage the objects in an AD domain. They create hierarchical structure within the domain, allowing to group objects according to their function or location. OUs don't have inherent security permissions and are not considered security principals. But permissions can be assigned to them to control access to the objects within them. 

Conclusion

This part talks about the basics of Active Directory in detail.