What is Proactive Threat Hunting?Threat hunting is designed to identify unknown threats within an organization’s systems. Unlike reactive cybersecurity methods, which involve responding to a known threat or attack, threat hunting is based on a hypothesis regarding a threat that the organization might be facing. Many organizations have a security strategy focused on detecting and preventing cyberattacks, but this isn’t enough for security. Threat hunting enables an organization to detect and respond to cyber threats that bypass an organization’s cyber defenses. This is essential for mitigating attacks by advanced cyber threat actors that have experience in evading common defenses. Every organization should engage in threat hunting as part of a defense-in-depth strategy. Proactive security enables an organization to detect missed attacks and can help to inform and improve preventative defenses.
Reactive vs. Proactive Threat Hunting
The tools and techniques used in threat hunting are similar to those used when responding to security incidents. In both cases, cybersecurity analysts perform an in-depth analysis of systems to identify indicators of attack. The main difference between the two processes is the starting point: a known incident vs. a hypothesis about a potential threat.
While proactive and reactive investigations use similar techniques, they also have significant differences. Some major differentiators include:
- Scope of Investigation: When investigating a known attack, the scope of investigation is relatively limited as some links in the attack chain are known and the analyst needs to work forward and backward from there. Threat hunting can include a much wider scope of investigation because it involves looking into a completely unknown potential threat.
- Application of Threat Intelligence: Both reactive and proactive investigations use threat intelligence, but they use this data in different ways. Reactive analysis can use threat intelligence to identify incoming or ongoing threats. In contrast, proactive threat hunting uses threat intelligence to determine which threats that an organization may face and how they can be detected.
- Depth of Investigation: An incident response investigation only needs to go far enough to verify a threat and collect any necessary information for remediation. Threat hunting, on the other hand, needs to prove or disprove a theory, which can be more difficult.
- Duration of Impact: The desired end result of incident response is the removal of a present threat. Threat hunting can not only help with the remediation of past attacks but can also help to close visibility gaps and improve defenses for the future.
Cyber Threat Hunting is a Proactive ApproachDone properly, threat hunting is a proactive approach to security. It is based on testing hypotheses about potential attacks rather than digging into threats that have raised alerts on enterprise security solutions. With the right tools, techniques, and processes – as outlined below -, a threat hunter can identify previously unknown threats within an organization’s IT architecture and close overlooked security holes to help prevent future attacks from occurring.
Proactive Threat Hunting ToolsThreat hunters need different tools and data sources than incident responders because they need to develop their own hypotheses and guide their own investigations. Threat hunters need an investigative portal focused on detecting the TTPs of known threats within an organization’s systems rather than retracing the path of a known intrusion from initial access to final objective.
Build a Threat Hunting HypothesisTo be proactive, threat hunters need to investigate a threat that they don’t already know exists. To do so, threat hunters develop a hypothesis about a potential threat that the organization may be facing based upon threat intelligence and knowledge of the organization’s IT environment. This hypothesis should be defined so that it can be proven or disproven based on the collection and analysis of security data within the company’s environment.
Back Your Hypothesis with EvidenceThe objective of a threat hunt is to prove or disprove the hypothesis, which requires data. Threat hunters may collect data from various platforms and data sources such as system and application logs, security tools, and dark web threat intelligence. All of this data should be aggregated for analysis, and the data sources and collection methods should be documented.
Analyze Your Collected DataAfter the necessary data has been collected, threat hunters can analyze it to prove or disprove their hypothesis. This could involve the development of new data analytics which can later be incorporated into defensive tools to provide visibility into this threat in the future. Proving or disproving a hypothesis may require multiple rounds of data collection and analysis if the original data set does not provide a definitive answer.
Document the HuntDocumentation is a key step in the threat hunting process. A threat hunt is an in-depth investigation of a potential threat, including data collection, the development of analytics to identify potential threats from this data, and proving or disproving that hypothesis. By documenting this process, a threat hunter provides a reference for the future. This not only helps to avoid duplicated effort but also makes it easier to repeat or improve on the process in the future.
The Bottom Line
Threat hunting is a vital, proactive component of a corporate cybersecurity strategy. It complements traditional, reactive cyber defense by enabling security analysts to seek out and remediate previously unknown vulnerabilities and intrusions into their environments.
A purely reactive cybersecurity strategy means that a company is always playing catch-up and providing attackers with a window to work toward their objectives and cause harm to the organization before threats are detected and remediated. As cyber threats become more sophisticated and automated, detecting them and remediating them will only become more difficult.
Threat hunting provides an organization with the ability to respond to cyberattacks that went undetected by existing defenses. By performing threat hunts, security analysts can not only remediate overlooked attacks but also develop methods for closing security visibility gaps, improving existing defenses and pursuing adversaries. Threat hunting not only helps to mitigate past and present attacks but also provides a path to improve security for the future.
More Useful Resources
Threat Hunting Guide: How To Protect Critical Assets Through Systematic, Proactive Threat Intelligence
3 Steps To Take Before Executing A Cyber Threat Hunt
How should you go about planning a cyber threat hunt? It comes down to three steps. By investing in each of these planning steps up front, your team can prepare itself both to execute the threat hunt relatively quickly and to ensure that the threat hunt answers your most urgent questions. Here’s a look at how to conduct those three steps of the planning process.