How securing Active Directory can prevent ransomware

Ransomware attacks are on the rise, posing a serious threat to global organizations. With an 80% increase in occurrences year-over-year, these cyberattacks have grown in frequency, complexity, and danger. This alarming rise is mostly due to ransomware-as-a-service tools, which drive risk levels through the roof. Additionally, cybercriminals are increasingly exploiting vulnerabilities in critical network components like Active Directory (AD).

90% of Fortune 1000 companies use AD to manage employee access and internal permissions. Thanks to its widespread use, Active Directory is a prime target for ransomware attacks.

Robust cybersecurity protocols around AD and other critical network components can prevent attackers from exploiting AD for ransomware incidents. To start with, IT leaders can find and fix vulnerabilities, implement multi-factor authentication, and adopt a zero-trust security model. All of these can seriously mitigate the risk of an attacker taking your AD hostage to accomplish a ransomware attack.

Why ransomware attacks target Active Directory

Active Directory (AD) is a prime target for ransomware attacks thanks to its central role in network management. We often talk about AD as the gateway to the rest of your network. As such, AD controls user access security.

This makes AD a high-value target for cybercriminals. When attackers take AD hostage, they essentially paralyze user access to numerous network resources. This, of course, leads to big operational disruptions.

Does ransomware encrypt Active Directory?

Of course, ransomware does not encrypt Active Directory itself. Attackers use Active Directory to access and encrypt connected hosts and domain-joined systems. LockBit 2.0 and BlackMatter are two popular ransomware families that attackers use to target AD.

Active Directory vulnerabilities give attackers the access they need to release a ransomware attack

When attackers breach AD with a ransomware attack as the goal, they have an advantage. Ransomware has a very short timeframe between the initial breach and impact. And AD's lack of visibility and context, essential for early detection, gives attackers plenty of time to carry out the ransomware attack.

Manual monitoring of AD is not only time-consuming, but often impractical. In practice, the gap in real-time monitoring means that most IT teams only become aware of a breach when it's too late.

Of course, all of this underscores the need for strong Active Directory ransomware protection. Ransomware can bring catastrophic consequences, exposing organizations vulnerabilities (some of which may be unknown, as AD becomes more complex).

But preventing ransomware in Active Directory involves more than just technical safeguards. It also requires cyber awareness training so users understand the importance of maintaining strict security protocols.

How do hackers attack Active Directory?

Ransomware attacks on Active Directory (AD) are intricate operations aiming to compromise connected hosts and domain-joined systems. Understanding these attacks is the first step towards effective Active Directory ransomware protection. Let's break down the key techniques attackers use to breach AD:

• Exploiting vulnerabilities: Attackers often exploit known vulnerabilities in AD. For instance, the CVE-2022-26925 vulnerability permits arbitrary code execution on AD servers, creating a significant security gap.

• Credential harvesting and brute force attacks: Attackers target human users, the network's most vulnerable point. Methods like phishing emails, keylogger deployment, and brute force attacks are common. These strategies aim to steal user credentials, compromising user access security in Active Directory. Once obtained, these credentials provide attackers with unauthorized access to sensitive AD data.

• Disabling Microsoft defender: The tactic involves turning off the built-in antivirus software on Windows systems. By disabling Microsoft Defender, attackers gain free rein to navigate the network and compromise AD without detection.

• Kerberoasting: An advanced attack exploiting the Kerberos protocol, where attackers request service tickets for service accounts. When decrypted, these tickets can reveal plaintext passwords. This is especially harmful since many service accounts have elevated privileges and static passwords.

• AD object permission exploitation: Attackers routinely exploit misconfigured AD object permissions. They can modify AD objects to grant themselves elevated rights or compromise the entire AD environment.

• Lateral movement and privilege escalation: Attackers inside the network attempt to move laterally, seeking vulnerabilities and escalating privileges. Techniques like Golden and Silver Ticket attacks exploit Kerberos tickets, granting extensive control over the domain.

• Using Ransomware-as-a-Service (RaaS): RaaS enables anyone to launch ransomware attacks without technical expertise. These kits include tools like exploit code and phishing templates, simplifying the attack process.

What does a typical Active Directory ransomware attack look like?

In a classic example of an Active Directory ransomware attack, threat actors try to get access to the network. They can use a variety of techniques to do that, such as:

• Fishing for user credentials

• Escalating privileges

• Moving vertically into the server network

Usually, the attackers' goal is to get administrative access rights and compromise a domain controller.

What does all this mean? Most importantly, these threats underscore the need for a strategy around preventing ransomware in Active Directory, including ransomware protection for Windows servers and cloud storage.

How to protect Active Directory from ransomware attacks

Facing a rising tide of ransomware threats, organizations must strategically strengthen their Active Directory (AD) infrastructure. This involves understanding AD vulnerabilities — particularly the common misconfigurations that attackers often exploit.

With a focus on comprehensive Active Directory security strategies, you can bolster your organization's defenses. Here, we explore actionable steps and practices to enhance Active Directory ransomware protection, reinforce user access security, and effectively prevent ransomware in Active Directory.

Conduct regular cyber awareness training

Enhancing Active Directory ransomware protection starts with investing in regular cyber awareness training. There's a human element to all cybersecurity, and preventing ransomware in Active Directory is no different.

• Recognize phishing attempts: Focus training on identifying phishing emails, a common entry point for ransomware. Teach employees to scrutinize emails for unusual sender addresses, unexpected attachments, and requests that seem out of the ordinary.

• Promote strong password practices: Instill the importance of strong, unique passwords to enhance user access security in Active Directory. Help employees understand the risks of weak passwords and the benefits of using robust, varied credentials.

• Understand protocols for suspected breaches: Ensure your team is familiar with the protocols for handling potential security breaches. Naturally, this process should include immediate reporting to IT teams for prompt action. With this, you can prevent a minor incident from escalating into a major attack.

• Empower every team member: Cyber awareness isn’t just for the IT department. Every employee plays a role in safeguarding the organization. Regular training sessions help foster a culture where cybersecurity is a shared responsibility.

• Simulate real-life scenarios: Run practical simulations, like mock phishing emails. These exercises prepare employees to question the authenticity of suspicious emails and attachments. Ultimately, they help your team to recognize and respond well to potential threats.

Regular cyber awareness training is a critical piece of a comprehensive security strategy (one that aligns people, processes, and technology). When you empower employees to act as the first line of defense against cyber threats, they can play a big role in raising your organization's overall security posture.

Keep Active Directory up-to-date

Regularly updating Active Directory is key to safeguarding it from ransomware attacks. Microsoft frequently releases security patches specifically for AD. Prompt installation of these updates reduces the risk of exploitation by attackers.

Exploits often focus on vulnerabilities found in outdated software. William Wright, founder of Closed Door Security and veteran pen tester sees outdated systems as one of the biggest vulnerabilities out there.

So, when you ensure that all systems, especially those associated with AD, are current, it's a big step toward boosting user access security in Active Directory. A routine patch management process also helps you stay ahead of potential security threats.

Sure, it can seem like a small detail, but being vigilant about the latest security updates keeps your AD environment functional and secure. A proactive approach makes your network a tougher target for cybercriminals, which naturally helps prevent ransomware in Active Directory.

Leverage threat intelligence in AD for early detection

Integrating threat intelligence into Active Directory security practices helps you to detect ransomware threats promptly. It focuses on analyzing and monitoring cyber threats in real time. As cyber threats evolve, having up-to-date intelligence allows you to adapt their defenses effectively and timely.

With threat intelligence, IT teams gain insights into unusual activity patterns within Active Directory. And, when you can identify key indicators of compromise, you can prevent a breach.

With more visibility, admins also can better maintain user access security, spotting and stopping suspicious activities, and preventing them from escalating into a full-blown ransomware attack.

By employing threat intelligence, you can also move beyond "just" defending your systems. You’ll proactively understand and anticipate potential threats. This helps fortify Active Directory against sophisticated ransomware attacks.

This ability transforms your organization’s security posture from reactive to preventive. And that significantly lowers the likelihood of successful ransomware exploitation.

Create an incident response plan for your AD

Developing an incident response plan is important to Active Directory ransomware protection. Since Active Directory (AD) is integral to your operations, a strong response plan is key to maintaining its availability. And if you do experience a compromise, the lack of access to connected applications can lead to a lot of downtime. This impacts employees, customers, and your company’s bottom line.

So, an incident response plan sets out clear procedures to outline how you will respond to cyber events. It focuses on swift detection, management, and recovery while minimizing damage.

The process involves several critical stages:

1. Detection and analysis: Employing cybersecurity technologies, including threat intelligence feeds, help in reporting suspicious activities. This stage determines if an incident has occurred and understanding its nature, extent, and magnitude.

2. Containment: This step varies depending on the attack type but aims to lessen the impact and halt further damage. Your cyber incident response team will use specific tactics to remove persistent access. This keeps ransomware from spreading within your AD network.

3. Eradication and recovery: Incident response teams focus on eliminating threats to restore normal operations. It includes collecting evidence and addressing vulnerabilities by modifying or fortifying the AD environment.

4. Post-incident activities: Documenting the process is the next step after addressing the incident. Thoroughly analyze the incident's root cause, any execution problems, and potential policy or procedural changes. This evaluation is invaluable for preventing future incidents and enhancing your overall Active Directory security posture.

Organizations may also consider frameworks like the Cybersecurity and Infrastructure Security Agency (CISA) guidelines or the SysAdmin, Audit, Network, and Security (SANS) framework.

Frameworks can structure your approach to incident response By ensuring cohesive and efficient action, you can keep your Active Directory network secure and functional, especially in ransomware scenarios with MSPs.

Mitigate risks with regular backups

Regularly backing up Active Directory (AD) data is an effective Active Directory ransomware protection strategy. AD is a critical service in networks for continuous business operations. Server crashes can disrupt local and cloud-based services, hindering access to essential applications and data.

But once you do regular backups, don't stop there. It's also important to test these backups for integrity. And don't forget to store them in secure, offsite locations beyond the reach of ransomware. Here are some key steps to consider:

1. Last resort recovery: Restore AD from a backup as a measure of last resort. However, last resort recovery is a necessary step to ensure business continuity in case of severe incidents.

2. Multiple domain controllers: Multiple domain controllers allow recovery, even if one fails. This setup provides a safety net but is not a substitute for regular backups. All controllers are susceptible to failures, database corruption, or ransomware attacks.

3. Active Directory recycle bin: Enable this feature to simplify the recovery of deleted objects. In some scenarios, this can also lower the need for immediate backups.

4. Thorough documentation: Maintain detailed records of your AD environment, backup policies, and disaster recovery plans for efficient recovery and managing user access security in the active directory.

5. Backup frequency and scope: Conduct daily backups of AD, and for large, dynamic environments, consider twice-daily backups. It's also necessary to have backups of at least two domain controllers per domain, including those holding the Operation master role.

6. Offsite backup: Keep an offsite backup of AD. This is critical for many reasons, but is even more important in scenarios involving ransomware, where the risks are great.

Of course, these backups require specific procedures, since AD is built on a specialized database. The backup process must occur online, and when Active Directory Domain Services are active, following specific backup protocols outlined in Ntdsbcli.h. While the built-in Windows Backup Utility doesn't support incremental backups, the overall backup approach helps in preventing ransomware in Active Directory.

Secure and track user access to the network

Effective Active Directory ransomware protection hinges on robust user access management.

First, implement multi-factor authentication (MFA) across all accounts. This enhances security, especially for RDP connections — common targets for ransomware attacks. So, if and when attackers obtain user credentials, MFA acts as a barrier, making unauthorized access significantly more challenging.

Then, update group memberships. This is not exciting, sorry. But it is a proactive way to manage user permissions. When you ensure access rights align with current roles and responsibilities, you lower the risk of outdated permissions leading to security breaches.

Next, apply least privilege access controls. The goal is to restrict users and administrators to the minimum access required for their roles. By doing this, you can limit the potential impact of compromised accounts — a key aspect of preventing ransomware in Active Directory.

You'll also want to monitor and log network activities. This helps identify unusual access patterns or changes, providing early warning signs of potential threats.

Last but not least, you'll want to secure administrator accounts. There are a few ways to do this, including:

• Block admin access to members’ servers and workstations.

• Prevent admin login as a batch job or a service.

• Restrict admin use of Remote Desktop Services on member servers and workstations.

When you enable MFA along with these strategies, you can create a more resilient defense against ransomware attacks. In other words, you're addressing not just the symptoms, but the root causes, of vulnerabilities in Active Directory.

Secure and track user access to files and folders

It's also important to adopt specific measures for file and folder access to safeguard Active Directory from ransomware. Role-based access control (RBAC) tailors file share access to user roles, limiting exposure to necessary data only. The approach aligns well with Active Directory's security framework.

File Integrity Monitoring (FIM) is also key to early threat detection. By alerting on unauthorized modifications, FIM helps identify potential security breaches promptly.

Encrypting sensitive files and folders adds a layer of security. So, even if attackers compromise other defenses, this security remains effective. The encryption acts as a deterrent against unauthorized access and data theft.

Admins also do well to prioritize regular audits of file access permissions to ensure ongoing alignment with organizational policies and role requirements. These audits help identify and correct any access discrepancies that attackers could exploit.

Another proactive step to set up real-time alerts for unusual file access patterns. These alerts enable immediate action upon detecting suspicious activities, contributing to a more robust defense against ransomware threats in Active Directory.