OSCP AD Set: Your Guide To Mastering Active Directory

Hey guys! So, you're diving into the world of the Offensive Security Certified Professional (OSCP) and specifically, the Active Directory (AD) set? Awesome! This is where things get super interesting. Forget just scanning and exploiting a single machine; you're now dealing with an entire domain. This article is your guide to navigating the OSCP AD set methodology. We'll break down the approach, covering everything from initial reconnaissance to full domain compromise. Think of this as your roadmap to conquering those OSCP AD challenges. Ready to get started?

Initial Reconnaissance: Your First Steps into the Domain

Alright, let's kick things off with initial reconnaissance. This is like the scouting phase in a video game – you gotta gather intel before you can launch an attack. In the OSCP AD set, this means understanding the target environment. Think of it like this: You wouldn't walk into a dark room without turning on the lights, right? Same principle applies here.

Your first step will be to identify the target's IP address and potentially some initial information about the operating system. You can often glean this information from the provided lab environment details, or any preliminary instructions. Once you have that, you'll need to identify open ports and services using tools like nmap. Running a basic nmap scan can give you a lot of information, like which ports are open (e.g., 80, 445, 3389) and what services are running on those ports (e.g., HTTP, SMB, RDP).

Next up, you'll want to dig a little deeper. Service enumeration is key. Use nmap scripts to gain further insights. For example, the smb-enum-shares.nse and smb-enum-users.nse scripts are super helpful for SMB enumeration. You can also use nmap scripts to identify the installed software versions to find potential vulnerabilities.

Don’t forget about web applications! If port 80 or 443 is open, start exploring those web pages. Look for interesting features, login portals, or any clues about the underlying technology (e.g., is it a WordPress site?). Tools like gobuster or dirb can help you discover hidden directories and files that might lead to further information or potential exploits. Also, check the HTTP headers for valuable information about the web server and its configuration. Understanding the web application can be a stepping stone for your access.

Finally, always try to grab any banners or version information the services provide. This gives you a clear indication of which versions of software are in use, which in turn helps you search for known vulnerabilities and exploits. Remember to take detailed notes during this entire process. You will need them later. Make sure you organize the results, so you can easily review them later. Initial reconnaissance is all about being thorough and methodical. The more you know at this stage, the easier the later steps will be. So, take your time, be patient, and embrace the process.

User Enumeration and Information Gathering: Uncovering the Secrets Within

Now, let's talk about user enumeration and information gathering. This is like trying to find the key to the castle. You need to identify users and glean any info that can help you with your goal of domain control. In the context of Active Directory, user enumeration is a crucial step. It helps you identify valid user accounts within the domain, which you can then try to target for exploitation.

One common technique is using rpcclient to enumerate users via the SAM (Security Account Manager) database. This tool can query the target system for a list of user accounts, giving you usernames and other potentially helpful details. Another useful tool is enum4linux, which is specifically designed for SMB enumeration and can help you identify users, groups, and shares. This tool is a goldmine for information. You can use it to determine if anonymous access is enabled, list shares, and get user information. The information found in this stage is the basis of your further exploitation path.

Don’t forget about the classic kerberos protocol. Sometimes, you can perform user enumeration by using tools that send requests to the Kerberos service. For example, you can try to get the pre-authentication information for a specific user to see if they're a valid user. This can provide some hints if the user exists. And then there are websites and file shares. Often, internal websites can reveal user information. So, explore any web applications running on the target and look for clues like user lists, employee directories, or default credentials that might have been left exposed.

In addition to enumeration, you'll also want to gather as much information as possible about the domain itself. This includes things like the domain name, the domain controllers, and the trust relationships between domains (if any). You can use tools like nltest and net view /domain to gather this information. Check the SYSVOL share! This is a shared folder on domain controllers that stores group policy objects. Misconfigurations in GPOs can sometimes expose sensitive information.

As you gather information, start creating a picture of the target domain's structure, including the domain controllers. This helps you to prioritize your efforts and develop more effective attack strategies. Remember, the more you learn about the environment, the better prepared you'll be to exploit it. Be creative. Think outside the box, and always test your assumptions. Also, pay close attention to any output of these tools. Errors can sometimes provide as much information as the successes. This information is a stepping stone to your next phase. So, put in your best effort at this stage.

Exploitation Techniques: Gaining a Foothold

Alright, it's time to talk about exploitation techniques. This is where you actually start leveraging your reconnaissance and information-gathering efforts. Think of it as the attack phase. You've identified vulnerabilities, and now you want to exploit them to gain initial access to a target system.

One of the most common initial access vectors is credential exploitation. If you've identified weak or default credentials during your reconnaissance, you can try to use them to log into services like RDP, SMB, or HTTP. This can give you a quick win. Password spraying, which is trying a small set of common passwords against many accounts, and password cracking are popular methods. If you have the user's password hash from NTDS.DIT, you can crack it using tools like hashcat or John the Ripper. Another great method is utilizing tools like mimikatz to harvest credentials from memory.

Next, let’s talk about vulnerability exploitation. This involves identifying known vulnerabilities in the services running on the target and then exploiting them to gain access. Tools like searchsploit can help you find exploits for specific software versions. A common example is exploiting a vulnerability in a web application to gain remote code execution (RCE). Once you have a foothold on a machine, your job is to escalate your privileges and move laterally.

When exploiting vulnerabilities, be careful. Test your exploits in a controlled environment first, if possible. Read the exploit code carefully to understand what it does and what impact it might have on the target system. Always try to understand the implications of your actions.

Don't forget about privilege escalation. This is about getting higher-level permissions on the compromised system. Local privilege escalation exploits are common. These exploits take advantage of misconfigurations or vulnerabilities within the operating system. Look for ways to escalate your privileges on the compromised host. You can use tools like PowerUp, WinPEAS, and LinPEAS to automate the enumeration of privilege escalation vectors. Also, examine the running services, installed software, and user permissions to identify potential vulnerabilities. The goal is to move from a standard user to a local administrator.

Once you’ve gained a foothold on a single machine, it’s time to move laterally. This is about pivoting from one compromised machine to another to gain access to other systems within the domain. Use credentials you’ve gathered to log into other machines or identify shared network resources that you can leverage. Your aim is to eventually compromise a domain controller, which will give you complete control over the entire domain.

Post-Exploitation and Lateral Movement: Expanding Your Control

Now, let's talk about post-exploitation and lateral movement. After you've gained your initial foothold, the game is far from over. This is where you work to expand your access and move deeper into the network. You must maintain persistence, gather credentials, and identify potential targets.

Gathering credentials is critical. You can use tools like mimikatz to dump credentials from memory. Look for cached credentials. These tools are the goldmines for credential harvesting. Also, inspect the registry for stored credentials. Pay attention to configuration files. Look for passwords or API keys that might have been left exposed. Your goal is to gather as many credentials as possible, since these are the keys to the kingdom.

Next, move laterally within the domain. Identify other machines and services that you can access using the credentials you've gathered. Use tools like PsExec or WMIC to execute commands remotely on other systems. Once you gain access to another machine, you can start the process of privilege escalation again. Try to gain access to domain controllers. These machines hold the keys to the kingdom.

Persistence is also important. You want to make sure you maintain access to the compromised systems, even if they're rebooted or the original vulnerability is patched. Create new accounts, install backdoors, or modify system settings to ensure that you can regain access later on. The goal is to establish multiple backdoors on multiple machines.

Documentation is key. Keep detailed records of your actions. Include the commands you ran, the results you observed, and the steps you took to achieve each objective. This documentation will be invaluable when you're writing your OSCP report, and it will also help you learn from your mistakes. Also, don't forget to clean up after yourself. Remove any traces of your activities. Delete logs, remove any backdoors, and restore the system to its original state. This is part of responsible penetration testing.

Domain Persistence and Privilege Escalation: Taking the Keys to the Kingdom

Here we go, guys! Time to talk about domain persistence and privilege escalation. At this point, you're not just trying to gain access; you're trying to own the domain. This means you need to be able to maintain your access and become a domain administrator. This is usually the ultimate goal in the OSCP AD set.

Firstly, let’s talk about domain persistence. This means maintaining your access to the domain, even if your initial foothold is discovered and removed. One common technique is creating a backdoor user account with domain administrator privileges. Another technique is modifying Group Policy Objects (GPOs) to execute malicious code on all domain-joined computers. You can also use scheduled tasks or services to maintain your access. By creating scheduled tasks, you ensure that your code runs periodically, even if the system is rebooted. This is important to ensure persistence in the network. If your initial access is a regular user, try to escalate your privileges to become a domain administrator. Look for misconfigurations, weak passwords, and vulnerable services. Also, monitor the network traffic and logs. This will help you identify any suspicious activity.

Next up, privilege escalation within the domain. Local privilege escalation is crucial. This is about escalating your privileges within a single machine. Once you have a foothold on a machine, try to escalate your privileges to gain administrator access. Leverage vulnerabilities and misconfigurations to elevate your access. Then, you can exploit them to move laterally to other machines. Once you gain access to a machine, gather credentials and move laterally. Your goal is to compromise the domain controllers. This will give you complete control over the entire domain.

Golden Ticket attacks are also a very powerful technique for gaining persistence. With a golden ticket, you can impersonate any user on the domain, including domain administrators. You can create a golden ticket, then use it to authenticate as a domain administrator. If you successfully compromise the domain controllers, you have complete control over the domain. This is the ultimate win in the OSCP AD set. This will allow you to create new users, modify group policies, and do whatever you need to do to complete your goals.

Concluding Your OSCP AD Journey: Wrap-Up and Report Writing

Alright, you've reached the end, guys. Now that you've successfully navigated the OSCP AD set, let’s talk about the wrap-up and report writing stage. You’ve put in the work, compromised machines, escalated privileges, and (hopefully) taken control of the domain. Now, it's time to document everything you've done.

When writing your report, the key is to be thorough, organized, and clear. Start with an executive summary, outlining the scope of the assessment, the vulnerabilities you exploited, and the overall impact. Provide a detailed timeline of your actions, including each step you took and the results you observed. Include screenshots of the initial reconnaissance, exploitation, privilege escalation, and lateral movement. Clearly explain each step you took to compromise the domain, including the tools you used, the commands you ran, and the vulnerabilities you exploited.

Make sure to document all the vulnerabilities you found and the impact of each vulnerability. Explain how you exploited each vulnerability and the steps you took to achieve your objectives. Include any recommendations for fixing the vulnerabilities and improving the security posture of the target environment. You need to provide a summary of the attack, the steps taken, and the impact of the attack. Include detailed explanations of each step, the tools used, and the commands executed. Also, document any findings that you discovered during the assessment. Include screenshots to support your findings and the impact of each vulnerability.

The report should also be structured, easy to read, and free of grammatical errors. Use headings and subheadings to organize your content. Use clear and concise language. Remember, the report is your way of communicating your findings to the client (in this case, the OSCP examiners).

Always remember to stay organized. Keep track of your progress, and take detailed notes. The more organized you are, the easier it will be to write your report. Finally, review your report carefully before submitting it. Make sure it's accurate, complete, and free of errors. This stage is just as important as the hands-on work, so take your time and do it right. Good luck, and go get that OSCP certification!