What is cyber threat hunting? Everything you need to know

What is threat hunting?

Threat hunting, also known as cyber threat hunting, is the proactive process of searching for signs of malicious activity within an organization’s systems and networks. Organizations face a wide range of threats, including malware, ransomware, phishing attacks, and zero-day vulnerabilities, many of which can bypass standard defenses. Instead of waiting for automated security tools to raise alarms, threat hunters actively look for evidence of these threats that may have slipped past traditional detection methods. 

How does cyber threat hunting work?

Cyber threat hunting starts with an  analysis of the organization’s internal system. Teams use automated security tools and data analysis to find anomalies that could indicate a larger security issue. 

After collecting this security data, threat hunters conduct a thorough investigation to determine if they notice any threats that had previously not been identified. If threats are found, action must be taken right away to re-secure the systems and prevent cyberattacks. 

Proactive threat hunting must be done on a regular basis to keep your systems secure. As your business grows and technology changes, it’s normal for new threats to emerge. Cyber threat hunting helps you stay one step ahead to prevent long-term cybersecurity issues. 

Threat hunting methodologies

Threat hunters use a variety of methodologies to find and eliminate potential threats. Let’s explore some of the most common threat hunting methodologies and how they work. 

Hypothesis-driven investigation

Hypothesis-driven investigation starts with a theory about a possible threat. Cybersecurity experts use threat intelligence to form a hypothesis about which threats might be present in the system. 

For example, if you notice that your competitors have been targeted by a certain threat, you might theorize that the threat is present in your systems as well. Then you would assess your systems to determine whether or not the hypothesis is correct.

Indicators of attack investigation

Indicators of attack (IoA) investigation begins by examining your cybersecurity data to identify potential signs of malicious intent or behavior. Rather than focusing solely on artifacts like unusual traffic patterns, IoAs encompass a broader range of activity, such as lateral movement, privilege escalation, or unauthorized access attempts. For instance, you might detect internal servers communicating unexpectedly with external addresses — a behavior that could suggest malware activity. If such IoAs are observed, you would then use threat detection tools to further investigate and identify any underlying threats within your systems.

Advanced analytics and machine learning investigation

One of the biggest challenges in any threat-hunting campaign is processing and analyzing large volumes of data in a relatively short amount of time. Luckily, behavioral analytics and machine learning technologies make this process much more efficient.

Many machine learning tools can analyze large data sets quickly, identifying anomalies and trends that can serve as the hypothesis for your threat hunt. They can also help you identify advanced persistent threats that require more sophisticated solutions. 

What are the steps of threat hunting?

Cyber threat hunting is a multi-step process that requires a targeted strategy and access to your organization’s cybersecurity data. Here are the standard steps to follow.

Step 1: Trigger

Combing through your entire system searching for possible threats isn’t efficient, and in many cases, it isn’t possible with the resources you have available. The cyber threat hunting process should begin with your team selecting a trigger to narrow things down. A trigger is a specific event, anomaly, or insight that prompts focus during the threat hunting process. Teams can choose a trigger using one of several different strategies.

The first option is to collect and analyze data from across your systems. For organizations with particularly large or complex IT setups, threat intelligence and machine learning tools can make this process easier. If you find any anomalies or concerning data points during this process, you can use these anomalies as the basis for your trigger.

Another approach is to create a hypothesis based on your research and understanding of the current cybersecurity landscape. For example, if you’ve recently discovered that a software program you use has a known vulnerability relevant to your operations, you might use that as the basis for your trigger.

Step 2: Investigation

The investigation phase involves taking a closer look at the trigger to determine if cyber threats are present. Depending on the context, this step may involve analyzing system logs, network traffic, or endpoint behavior to identify any signs of malicious activity.

Endpoint detection and other threat hunting tools are also helpful during the investigation process. Using technology speeds up the investigation phase and can help you find potential threats you may have missed while reviewing your systems manually.

It’s important to document your findings thoroughly during the investigation phase. Detailed records will make the resolution phase more straightforward and can help you avoid these cybersecurity threats in the future.

Step 3: Resolution

The final stage in the threat-hunting process is resolution. During this phase, you will address any problems or concerns you identified during the investigation. This step also allows you to make broader changes to your cybersecurity strategy as needed.

For example, during your investigation, you might find that your internal access control system isn’t strong enough, leaving your organization vulnerable to an insider threat. Reviewing user logs and using endpoint detection tools can confirm the problem discovered during the investigation phase.

In this situation, the resolution phase might involve implementing new access control strategies with a least-privilege approach. This approach limits the number of employees accessing your system’s sensitive data, reducing the possibility of an internal data breach.

In addition to addressing the problem directly, you can use the resolution stage to make large-scale changes to your overall cybersecurity plan. This step might include shifting your system configuration, investing in new IT software programs, or changing your system monitoring approach.

Cyber threat hunting types

Cybersecurity experts use many different types of cyber threat hunting. The right approach for your organization will depend on your security needs and the resources you have available. 

Structured hunting

In structured hunting, threat hunters follow a predefined approach based on existing threat intelligence. In particular, this technique uses existing tactics, techniques, and procedures (TTPs) to identify threats. One example of this is the MITRE ATT&CK database and guidelines for classifying cyberattacks. This accessible database helps hunters detect advanced persistent threat behavior before it escalates. 

Unstructured hunting

In unstructured threat hunting, hunters analyze existing security data to look for unusual activity. While they don’t start with a predefined hypothesis, their investigation is guided by experience and real-time observations of suspicious patterns or behaviors. For example, hunters might notice an unexpected administrative login at midnight, without prior alerts. This login could indicate that someone outside of the organization has gained access to the system. 

Situational- or entity-driven hunting

Situational- or entity-driven hunting focuses on specific assets or users that are at risk. It can also focus on known threat actors that could be targeting your systems. For example, if a phishing attack is currently targeting top-level employees in your industry, you might investigate your executive accounts for unusual activity. 

Threat hunting tools

Using various tools makes the entire process more efficient and can help you catch potential threats you would have missed on your own. Let’s take a look at some of the most popular solutions for threat hunting.

SIEM

SIEM stands for security information and event management. These automated security programs collect and analyze security data from various points throughout your system. When a security event occurs, it typically generates an alert and, depending on the system configuration, may trigger an automated response — either of which could serve as a starting point for a threat hunt.

MDR

MDR stands for managed detection and response, a service provided by cybersecurity professionals. It is an excellent option for organizations that lack the resources to collect threat intelligence in-house. MDR is a fully managed security service that typically includes continuous monitoring, threat detection, and incident response. While some MDR providers offer proactive threat hunting, others focus more on reactive measures when threats are detected.

EDR

EDR stands for endpoint detection and response. EDR programs monitor activity on your organization’s endpoint devices, such as a computer, mobile device, or even an IoT device. These software programs help you identify cyber threats coming specifically from these devices.

NDR

NDR stands for network detection and response. These software programs are similar to EDR but focus on network security rather than endpoints. A program that combines aspects of EDR, NDR, and other system monitoring tools is called XDR, which stands for extended detection and response.

Security analytics

Security analytics tools use advanced data analysis to identify and respond to cybersecurity threats. These tools synthesize data from a number of sources, including network traffic logs and endpoints. 

These tools apply advanced analytics techniques and often use artificial intelligence and machine learning to operate efficiently. With security analytics, you can find anomalies that you might have missed with manual threat detection strategies. 

What is the difference between cyber threat hunting and threat detection?

The terms “threat hunting” and “threat detection” are often confused, but they refer to different aspects of cybersecurity. Many organizations use both passive threat detection tools and proactive threat hunting strategies to keep their systems safe. 

Here are the differences between cyber threat hunting and threat detection.

Together, threat hunting and threat detection help create a more complete defense. With the right tools and a proactive mindset, your team can stay ahead of potential threats and keep your systems safer in the long run.