Are you confident your network is secure?
In today’s cyber landscape, waiting for breaches to happen is a way to disaster. The average time to detect an attacker lurking within a network is 10 days, according to a 2024 Mandiant Special Report. While dwell time statistics, particularly those found in reports like Mandiant’s M-Trends, offer valuable insights, it is important to consider the context in which they are presented.
In my view, these reports often reflect the experiences of organizations with mature incident response capabilities. These organizations tend to be larger or more frequently targeted by sophisticated attacks, making them more likely to engage firms like Mandiant. This can create a potential bias in the data, as it may not fully represent the experiences of smaller or less mature organizations, which often lack the same resources and expertise.
This blog post explores why continuous network intrusion hunting is crucial and how to implement it effectively.
Why Reactive Security Isn’t Enough
Traditional security measures like Intrusion Detection Systems (IDS), Endpoint Detection and Response (EDR), and Security Information and Event Management (SIEM) are essential, but they’re not foolproof. Sophisticated attackers are skilled to evade these automated defenses, buying themselves precious time within your network. This is where proactive threat hunting comes in. Instead of simply reacting to alerts, threat hunters assume a breach has already occurred and actively search for the signs. This proactive approach significantly reduces dwell time, minimizes damage, and speeds up recovery.
Threat Hunting a step-by-step approach
Effective threat hunting requires a structured approach. Following is a breakdown of the key steps:
1. Establish a Baseline: Know your “Normal”
Before you can identify anomalies, you need to understand what “normal” looks like. Establishing a baseline of your network traffic, user behavior, and application activity is crucial. This baseline acts as a benchmark against which you can compare current activity to detect deviations. Think of it like knowing the typical routine operations in your office. A sudden silence in a normally busy area or an unusual noise, will immediately grab your attention. A network baseline serves the same purpose especially when coupled with robust asset management and network topology, allowing you to quickly identify unusual or suspicious activity that deviates from the established norm.
2. Data Collection: Gathering the Clues
Threat hunters rely on Indicators of Compromise (IOCs) the pieces of data that suggest malicious activity. To find these clues, you need comprehensive data collection. This involves gathering network flow data, packet captures, logs from various sources (servers, endpoints, network devices), and alerts from your security tools. SIEM solutions play a critical role here, aggregating and correlating data from across your network for efficient analysis. Think of it as assembling a detective’s evidence board.
3. Searching and analyzing to connecting the dots
With data collected and aggregated in your SIEM, the real hunting begins. This involves searching for IOCs, correlating events, and analyzing logs to understand the attacker’s movements. Leveraging analytics and machine learning can significantly enhance this process, helping to identify subtle patterns and anomalies that might otherwise go unnoticed. Frameworks like MITRE ATT&CK and the NSA Technical Cyber Threat Framework (NTCTF) provide valuable guidance on attacker tactics and techniques, helping hunters focus their search. The Pyramid of Pain helps prioritize IOCs, from easily changeable hashes to more impactful Tactics, Techniques, and Procedures (TTPs).
4. Incident response to recover
When a hunt uncovers malicious activity, it’s time to take actions. A well-defined incident response plan is essential for containing the breach, eradicating the threat, and restoring your systems. This involves assessing the scope of the attack, collecting evidence, and implementing your recovery procedures. Think of it as executing a well-rehearsed emergency plan.
5. Penetration Testing a valuable ally
While this isn’t strictly a threat hunting practice, penetration testing plays a crucial role in strengthening your defenses. By simulating real-world attacks, penetration testers can identify vulnerabilities and weaknesses in your network, providing valuable insights for your threat hunting team. It’s like a fire drill for your security team.
Challenges and Considerations
Threat hunting isn’t without its challenges. The vast amount of data, the cost of storage, the need for skilled hunters, and the difficulty of inspecting encrypted traffic are just a few of the hurdles. However, the benefits compensate the challenges.
Be Proactive Not Reactive
In current ever-evolving cyber threat landscape, proactive threat hunting is no longer a luxury which is only for large organization but it’s a necessity. By continuously searching for intruders, you can significantly reduce dwell time, minimize damage, and protect your organization from costly breaches. Don’t wait for the next attack but start hunting today.
