53. Threat Hunting: Proactively Seeking Out Cyber Threats

Threat hunting is an advanced cybersecurity practice that aims to proactively seek out and identify threats within a network before they can cause significant damage. Unlike traditional reactive measures, threat hunting pushes cybersecurity professionals to take an active role in seeking out threats that may have evaded automated security measures. This interactive lesson provides insights into the concept and practice of threat hunting, underpinning its importance, and highlighting best practices.

Defining Threat Hunting

Threat hunting is a proactive security strategy that involves looking for threats that may be present in a network but have so far remained undetected. The aim is to close the time gap between a compromise and detection, hence reducing the potential damage a successful attack could have on an organisation’s resources or information. Whereas traditional security measures tend to focus on prevention and automated detection, threat hunting adopts a more proactive, human-led approach to cybersecurity.

The Importance of Threat Hunting

In an era where cyber threats are increasing both in complexity and frequency, traditional defence mechanisms such as firewalls, intrusion detection systems, and antivirus software, while necessary, are often insufficient. Sophisticated threats, including Advanced Persistent Threats (APTs) and zero-day exploits, can bypass these security controls and lay dormant within a network, undetected for significantly long periods.

According to a study by Ponemon Institute, the average time to identify and contain a breach in 2020 was 280 days.(source) This figure underpins the necessity for organisations to adopt proactive threat hunting strategies, reducing the dwell time of cyber threats and minimising potential damage.

Steps in Threat Hunting

The threat hunting process can generally be divided into four key steps:

1. Hypothesis Formation: This involves generating an educated guess or assumption about the activities of probable threats. This could be based on intelligence about latest threat behaviour or patterns spotted in network logs.
2. Data Collection: In this step, relevant data from network logs, threat intelligence feeds, and other operational data is collected and analysed.
3. Investigation: The collected data is then carefully examined to validate or dismiss the hypothesis. Advanced analytic tools and techniques can be used to identify abnormal activities that may signify an undiscovered threat.
4. Action: If a threat is discovered during investigation, steps are taken to remove it and strengthen defences to prevent a similar future breach. If no threat is found, the findings still contribute valuable insights that can improve future hypotheses and investigations.

Key Elements of Effective Threat Hunting

For threat hunting to be successful, certain key elements must be in place and effectively utilised. These include:

1. Solid Understanding of Baseline Behaviour: Knowing what is normal for your network is crucial to spotting what is abnormal. This requires in-depth understanding of daily processes, traffic flows, user activities, and system configurations.
2. Use of Threat Intelligence: Threat intelligence feeds provide valuable information about the current threat landscape, including new threat actors, tools, techniques, and tactics (TTPs) in use.
3. Effective Security Tools: Tools for log management and data analytics, among others, are essential for collecting and processing relevant data during investigations. Some organisations also use predictive analytics tools to generate hypotheses.
4. Trained Cybersecurity Staff: Threat hunting requires advanced skill sets and experience. Your cybersecurity staff should be capable of not just using security tools effectively, but also thinking critically and creatively to spot hidden threats.

Threat Hunting Best Practices

In closing, while practices may differ depending on specific environments and threat landscapes, the following best practices can typically benefit all threat hunting operations:

• Regularly updating threat intelligence feeds to stay aware of the latest threat trends.
• Keeping all security and data analysis tools up-to-date to improve their effectiveness and efficiency.
• Regularly training staff on the latest threat trends, hunting tools, and techniques.
• Continuously refining and improving hunting processes based on lessons learned from each hunting cycle.

Threat hunting represents an advanced, proactive approach to achieving cybersecurity. While it requires significant investment in tools, skills, and time, it offers the potential to reduce the often devastating impact of successful cyber-attacks. As cyber threats continue to evolve, so too must our strategies for defending against them — and threat hunting is a significant step in the right direction.