Threat hunting with Splunk is a powerful way to proactively detect and respond to cyber threats. Splunk is a data analytics platform that can be used to analyze large volumes of security data from a variety of sources, including security logs, network traffic, and endpoint data.
By using Splunk to hunt for threats, organizations can identify and mitigate malicious activity that may have evaded traditional detection systems. Splunk also provides the ability to automate threat-hunting tasks, which can help organizations to improve their security posture and reduce their risk of being compromised.
In this blog post, we will provide a how-to guide for threat hunting with Splunk. We will discuss the following topics:
- What is Threat Hunting?
- How to use Splunk for Threat Hunting?
- Utilizing Splunk's Search Processing Language (SPL)
- Developing queries
What is Threat Hunting?
Before we dive into Splunk-specific techniques, it's important to grasp the concept of threat hunting. Threat hunting is not solely reliant on automated tools or predefined signatures. It involves human expertise and intuition to uncover anomalies, threats, and vulnerabilities that may evade automated detection systems. The process is iterative, requiring continuous refinement of hunting techniques.
What is Splunk?
Splunk is a software platform widely used for searching, monitoring, and analysing machine-generated data. It is particularly valuable for organizations that need to make sense of large volumes of data from various sources, such as logs, events, and metrics generated by IT systems, applications, servers, network devices, and more.
How to use Splunk for Threat Hunting?
If you're new to Splunk, start by installing and configuring it according to your organization's needs. Ensure data sources, such as logs from firewalls, servers, and endpoint devices, are ingested into Splunk. Splunk's Universal Forwarders are a handy tool for this purpose.
Defining your objectives
Effective threat hunting begins with a clear objective. Define what you're looking for, whether it's unusual network traffic patterns, suspicious user behavior, or signs of known malware. A well-defined objective will guide your hunting efforts and help you narrow down the search.
Utilizing Splunk's Search Processing Language (SPL)
Splunk's Search Processing Language (SPL) is your gateway to extracting valuable insights from your data. Mastering SPL is essential for effective threat hunting. Here are some SPL commands you can use:
- index: Specify the index you want to search in.
- source: Target specific log sources.
- sourcetype: Narrow your search to specific log formats.
- search: Start your hunt with a search query.
- stats and eval: Perform statistical analysis to identify anomalies.
- timechart: Visualize time-series data to detect patterns.
- rex and regex: Use regular expressions for custom data extraction.
- lookup: Enrich your data by adding information from external sources.
Crafting effective search queries is where the art of threat hunting comes into play. Consider the following tips:
- Start broad and refine your search iteratively.
- Look for outliers, anomalies, and deviations from baselines.
- Incorporate threat intelligence feeds to identify known indicators of compromise (IoCs).
- Use historical data for trend analysis.
- Collaborate with colleagues and share insights.
Correlation and visualization
Splunk's real power lies in its ability to correlate data from various sources. Use correlation searches to connect the dots between seemingly unrelated events. Visualization tools like Splunk's dashboards and reports can help you spot trends and anomalies quickly.
Building custom threat models
Every organization is unique, and so are its threat-hunting needs. Consider building custom threat models tailored to your specific environment and threat landscape. These models can help automate parts of the hunting process and ensure consistency.
Threat hunting is an evolving field. Keep up with the latest cybersecurity trends, attend workshops, and participate in threat-hunting communities. Splunk also offers numerous training resources and certifications to help you become a Splunk expert.
Threat hunting with Splunk is a powerful approach to bolstering your organization's cybersecurity posture. It combines human expertise with the capabilities of a robust platform to proactively seek out and mitigate threats before they cause harm. Remember that threat hunting is an ongoing process, and as you gain experience, your hunting techniques will become more refined and effective.
Disclaimer: This guide is for informational purposes only. Always adhere to your organization's policies and guidelines when performing threat-hunting activities.
Being a Splunk Singapore partner, Positka specializes in high-end technology solutions to help businesses improve their overall IT infrastructure. Founded in 2014, our services include Splunk Services, Cybersecurity & Risk Management, Security Awareness Training, Managed security services, Lean Process Optimization, Robotic Process Enablement Services and Solutions while partnering with other top-tier companies like SentinelOne and so on. We are headquartered in Singapore and operate across India, the US and UK as well.