Master the Threat Hunting Process: A Proactive Approach

Cyber threat hunting proactively looks for hidden threats in your network. This goes beyond automated tools, using human analysis to find advanced attacks. This guide covers the cyber threat hunting process, tools and techniques, and tips for implementation.

What is the Threat Hunting Process?

A threat hunting process is an active approach where security analysts, including cyber threat hunters, systematically search through network, cloud, and endpoint logs to detect indicators of compromise and threat actor tactics, techniques, and procedures, including advanced persistent threats. 

Unlike traditional threat detection methods which rely on automated tools and predefined signatures, threat hunting involves actively looking for all events that can affect the system. 

The cyber threat hunting process is a proactive, multi-stage approach aimed at identifying and mitigating potential threats within a system.

Proactive cyber threat hunting differs by being proactive. It allows organizations to:

• Stay one step ahead of the latest threats

• Respond to potential attacks quickly

• Assume the adversary is already in the system

• Investigate unusual behavior to find malicious activity

• Plug the security holes

• Neutralize threats before damage is done

This is critical to overall security and data protection.

Cyber threat hunting requires the expertise of seasoned security professionals, lots of data, and robust analytics. Threat hunters can use more storage to get a better understanding and context of threats from live and past data.

This helps to completeness and accuracy of their investigation and analysis. Human threat hunters are key to finding complex targeted attacks that automated tools miss, hence their importance in the threat hunting process.

In short, threat hunting is:

• Being one step ahead of the bad guys

• Responding to potential threats in time

• A part of a solid security strategy

• Focusing on detecting and responding to unknown and unmitigated threats.

Threat Hunting Process

The threat hunting process is broken down into three main stages:

• a trigger 

• an investigation

• and a resolution

Each stage plays a critical role in detecting, investigating, and mitigating cyber threats.

The trigger phase involves gathering information and forming hypotheses about threats based on known vulnerabilities or anomalies. This can be triggered by new threat intelligence or observed anomalies in the security data feed.

In the investigation phase, threat hunters use various approaches such as data collection and analysis to find and validate suspicious activity. This phase is supported by standard incident detection, response, and remediation processes.

Finally, the resolution phase involves responding to the threats and remediating the affected systems. Each of these steps is critical to the overall threat hunting process.

Step 1: Hypothesis

The hypothesis is the starting point of the threat hunting process. This first step is critical as it sets the direction for the entire hunt. 

Hypotheses can be triggered by announced vulnerabilities, zero-day exploits, or anomalies in the security data feed. Business-related risks, trends, and vulnerabilities analysis can also be a starting point specific to an organization's environment.

Human-driven threat hunting relies heavily on hypothesis-driven approaches as automation cannot replace the intuition and expertise of experienced threat hunters. Through hypothesis, threat hunters can look into intrusions that traditional detection mechanisms miss, hence a more complete and proactive approach to uncovering cyber threats.

Step 2: Data Collection and Analysis

After the hypothesis, data collection and analysis follow. The quality of the data collected is key as incomplete data can give a false sense of security. 

Digital Forensics and Incident Response (DFIR) skills are essential for threat hunters to collect and analyze relevant artifacts that can indicate malicious activity. Threat hunters collect:

• Indicators of Compromise (IoC)

• Data breaches

• Malware

• Trojans

Analyzing live monitoring data and using behavioral analysis helps to detect anomalies that may be cyber threats. Advanced analytics tools are used to process this data to give insights to the threat hunters to investigate.

Step 3: Investigation

Most of the threat hunting work happens during the investigation phase. In this phase, threat hunters use various tools to review system logs and investigate anomalies to uncover cyber threats. A common assumption during investigation is that the system is compromised or vulnerable and that needs to be validated or disproven through the hunt.

The focus is on proactively looking for anomalies to prove or disprove the hypothesis. The collected data is used to answer the 'Who?', 'What?', 'When?', 'Where?' and if possible 'Why?' of the anomalies found. This deep dive helps to understand the nature and extent of the potential threat.

Step 4: Response and Remediation

Once a cyber threat is identified, the next step is response and remediation. The goal of the response step in the threat hunting process is to stop the attack as soon as possible. This involves mitigating the detected threat and updating the incident response plan to prevent similar attacks in the future.

The information gathered during the resolution phase can be used to predict trends, prioritize and remediate vulnerabilities, and improve security. This continuous cycle ensures the organization is better prepared for future threats and can respond faster.

Step 5: Reporting and Improvement

Reporting and improvement are the final steps of the threat hunting process. Documenting findings in both short and long-form is necessary to share with different departments and the infosec community about cyber threats.

This documentation helps to improve the threat hunting process and to apply lessons learned to future hunts.

Types of Threat Hunting Approaches

Threat hunting can be done through multiple approaches, each with its benefits depending on the situation. 

Structured hunting is a methodical approach that uses predefined criteria or intelligence frameworks like MITRE ATT&CK to look for specific cyber threats or Indicators of Compromise (IoC). This is often triggered by Indicators of Attack (IoA) and Tactics, Techniques, and Procedures (TTP) of the attackers.

Threat hunting can be done in different ways:

1. Structured threat hunting: This involves following predefined hypotheses and looking for specific Indicators of Compromise or known attack patterns.

2. Unstructured threat hunting: This allows threat hunters to think outside the box and look for non-specific or anomalous activity without predefined hypotheses.

3. Situational or entity-driven hunting: This is focused on specific events or contextual factors that may be a higher risk to the organization's security.

Each of these can be tailored to an organization's needs so you get a comprehensive threat hunting strategy.

Structured

Structured hunting follows a methodical approach to finding threats by looking at known Indicators of Compromise (IoC) and Indicators of Attack (IoA). This uses predefined criteria and intelligence frameworks like MITRE ATT&CK to find adversary TTPs, so a thorough and targeted hunt.

Unstructured

Unstructured hunting relies heavily on the threat hunter's intuition and expertise to look for non-specific or anomalous activity without predefined hypotheses. This allows threat hunters to think outside the box and find signs of malicious activity that may not fit traditional IoC or threat profiles, useful in a dynamic threat landscape.

Situational

Situational hunting is triggered by specific events or contextual factors, such as unusual network activity or emerging threat intelligence. This targeted approach is focused on specific entities or situations that may be a higher risk to the organization's security so a more precise and faster threat hunt.

Tools and Technologies for Threat Hunting

Threat hunting requires a whole toolbox of tools and technologies to uncover cyber threats. Security Information and Event Management (SIEM) software provides visibility and a history of activity in an organization's IT environment so you can identify abnormal activity and take immediate action. SIEM tools ingest cyber threat intelligence feeds so you are ready to use alerts and dashboards for threat hunting.

Endpoint Detection and Response (EDR) solutions give you:

• Visibility into endpoint activity

• Detection of threats that traditional antivirus misses

• Advanced analytics and machine learning to process vast amounts of data

• Detection of anomalies that may indicate malicious activity

These help with threat hunting.

Security Information and Event Management (SIEM)

SIEM tools give you:

• Real-time logs from applications and hardware

• Identification of abnormal activity

• Immediate action to mitigate threats

• Integration with threat intelligence to proactively identify threats

• Fast response to incidents

Threat intelligence with SIEM allows you to proactively identify and mitigate threats so security teams can respond faster to incidents.

Converged SIEM helps threat hunters by allowing query-based investigations, such as searching for all instances of a specific data label. SIEM tools also allow you to import lists of malicious URLs, hashes, and IPs to save time during threat hunting so it's faster and more effective.

Endpoint Detection and Response (EDR)

EDR (Endpoint Detection and Response) is used by threat hunters during the investigation phase:

• Consolidate endpoint security and billions of system events into one pane of glass for threat identification

• Visibility into endpoint activity

• Detect threats that traditional antivirus misses

EDR tools are a must-have in the threat hunting process.

Cyber Threat Feeds

Threat hunting integrates cyber threat intelligence feeds, enabling analysts to utilize alerts and dashboards effectively for detecting and investigating threats.

A good example of this are our own Hunt.io threat intel feeds, which offer comprehensive coverage of IP addresses, domains, and hostnames associated with malicious activities. These feeds (including C2 infrastructure feeds) provide real-time insights and enhance the ability to proactively identify and mitigate threats across your network.

Machine Learning and AI for IOC detection

Using advanced analytics and machine learning in the threat hunting process allows you to use automated security tools so less manual effort and more threat detection.

Machine learning can process vast amounts of data to detect anomalies which can then become hunting leads, making threat hunting more effective.

Additionally, our IOC Hunter leverages machine learning to convert trusted public research into machine-readable formats, enriching investigations with deep context and enabling quicker and more accurate identification of indicators of compromise.

Skills and Traits of a Threat Hunter

Threat hunters need a mix of technical skills, analytical thinking, and personal attributes. Technical skills are required to understand cybersecurity threats and network analysis so you can detect cyber threats comprehensively. Analytical thinking helps you identify and investigate anomalies and strong communication skills to share findings with other teams and stakeholders.

Humility is key for threat hunters so you can learn and not be biased which is critical for accurate and effective threat hunting. By having these skills and traits you can mitigate threats and protect your organization.

Technical Skills

For threat hunters technical skills are a must. Here are some skills to focus on:

• Programming skills, especially in Python, to create tools and automate workflows.

• Familiarity with at least one scripting language and one compiled language to handle various tasks.

• Knowledge of networking and common network protocols to analyze data flows and identify abnormal activity

Threat hunters should also be familiar with red teaming tools and techniques used by adversaries to gain access to networks. In the world of cybersecurity, deep technical knowledge is required to analyze complex systems and identify threats so threat hunting can be comprehensive and effective.

Analytical Thinking

Analytical thinking is required for threat hunters to identify and investigate anomalies. Here are the steps:

1. Create a baseline of network traffic or system activity to recognize patterns of abnormal activity.

2. Know what is 'normal' in your environment.

3. Develop an investigative mindset to recognize deviations that could be threats.

By following these threat hunting steps you can identify and respond to threats.

Communication Skills

For:

• explaining technical jargon to a broad audience within the organization

• working with different stakeholders, including IT, legal, and business teams

• improving threat hunting

• responding to threats identified

Best Practices to Improve Threat Hunting

Following best practices like training, collaboration, and leveraging threat intelligence is key to improving cyber threat hunting. Having sufficient resources, experienced people, systems, and tools is critical for threat hunting. Knowing what's 'normal' in your organization helps you to distinguish between real threats and anomalies making the hunt more accurate and effective.

Automation in cyber threat hunting helps to use staff and resources more efficiently and adds agility to a threat response. Following the Observe, Orient, Decide, Act (OODA) loop helps to respond to threats systematically and proactively.

Training and Skill Development

Continuous training helps threat hunters to stay ahead of the latest threats and respond quickly to potential attacks. Training in malware reverse engineering and adversary tracking is key to threat-hunting skills. Certifications like Certified Cyber Threat Hunting Professional (CCTHP) or Certified Ethical Hacker (CEH) will help to improve skills.

Collaboration and Information Sharing

Internal threat-hunting collaboration involves working closely with different departments within the organization such as IT, legal, or business teams to contextualize threats and assess the impact on specific business operations. Human interaction and input within the organization help to resolve faster and more accurately and remove manual errors and duplication.

Sharing threat intelligence with external entities like computer emergency response teams (CERTs) will improve detection and response. Using standards like Trusted Automated eXchange of Intelligence Information (TAXII) and Structured Threat Information eXpression (STIX) enables automated sharing of threat data and provides insights into attackers' latest TTPs to aid threat hunting.

Threat Intelligence

The information gathered from threat hunting can be used to predict trends and prioritize vulnerabilities. It can also be used to improve overall security. Threat intelligence is used to focus on high-impact malicious activity first so the most critical threats are addressed first.

Threat intelligence involves using known Indicators of Compromise (IOCs) and Indicators of Attack (IOAs) to find potential hidden attacks. Threat hunters can find potential threats or vulnerabilities by combining threat intelligence with relevant data and context about the network entities. This makes the threat hunting process more comprehensive and effective.

Threat Hunting as a Service

Threat hunting as a service means:

• Outsourcing threat detection and response to expert service providers

• Continuous threat monitoring and advanced threat detection for the organization

• More cost-effective as no need to train internal staff on new platforms and tools

• Managed service providers have access to advanced tools and technologies that individual organizations can't afford to have on their own

This is for organizations who want to strengthen their security.

Organizations that are not staffed and equipped to do continuous 24/7 threat hunting can still hunt for unusual network activity and hidden cyber threats by using managed security solutions. Managed threat hunting services provide continuous monitoring and analysis which is critical for organizations that can't maintain 24/7 in-house threat detection and response.

When to use Managed Services

Organizations with limited in-house cybersecurity resources or expertise should use a threat-hunting service. Companies struggling to run effective threat intelligence programs due to a lack of dedicated personnel may benefit from managed services.

Selecting the Right Service Provider

When selecting a managed service provider make sure they understand your cyber threat intelligence requirements. Evaluate the threat intelligence platform and technologies used by the provider to ensure they meet your needs. Assess the skill sets and expertise of the analysts, technical and soft skills.

Look for providers that offer customized solutions for your organization's security needs. Evaluating the provider's response time and track record in mitigating threats will help you make a better decision.

Threat Hunting in Action

Organizations have used threat hunting to detect and neutralize potential cyber threats before they can cause significant damage. 

Our research, "A Simple Approach to Discovering Oyster Backdoor Infrastructure," uncovered tactics and infrastructure used by the Oyster backdoor. This study highlighted the importance of identifying hidden malicious activities.

In another study, "SEO Poisoning Campaigns Targeting Browser Installers and Crypto Sites," we exposed malware distribution methods using SEO poisoning. The investigation revealed how attackers manipulate search engine results to spread threats.

Our investigation, "The Secret Ingredient: Unearthing Suspected SpiceRAT Infrastructure via HTML Response," revealed SpiceRAT infrastructure through HTML analysis. This research demonstrated the value of examining HTML responses for hidden threats.

Lastly, the research, "ProxyLogon and ProxyShell Used to Target Government Mail Servers," highlighted the exploitation of vulnerabilities to target government mail servers. This study underscored the need for proactive vulnerability management.

These examples underscore the vital role of threat hunting in safeguarding against sophisticated cyber threats, using advanced tools and expert analysis to protect digital assets.

Conclusion

In summary, the cyber threat hunting process is key to staying ahead of sophisticated threats. By understanding the proactive nature of threat hunting and following the steps from hypothesis to reporting to improvement, organizations can detect and mitigate hidden threats. Using the right tools and technologies like SIEM, EDR, and machine learning will further enhance the threat hunting process.

Good threat hunters have technical expertise, analytical thinking, and strong communication skills to protect their organization. Following best practices like continuous training, collaboration, and using threat intelligence will help to improve threat hunting.

Upgrade your threat hunting with Hunt.io's Advanced Threat Hunting platform. Schedule a demo now to see its full potential.