DEV Community

AJ
AJ

Posted on

Exploring Zeek: A Powerful Network Security Monitoring Tool

Zeek is a powerful and flexible network security monitoring tool used by analysts to process and analyze network traffic. It operates by inspecting network packets and generating logs that provide detailed insights into network events. This blog post will guide you through Zeek’s structure, its primary capabilities, and practical use cases.

The Layers of Zeek
Zeek has two main layers:

Event Engine
The Event Engine processes packets, breaking them into smaller components like source and destination addresses, protocol information, session details, and more. This is the foundational layer where data is prepared for deeper analysis.

Policy Script Interpreter
This layer uses Zeek scripts to describe event correlations. It allows analysts to define custom logic for event analysis and automate responses to specific network activities.

Here’s a potential draft for your blog post about Zeek. It adheres to your guidelines of being written in simple academic English, structured for DEV compatibility, and including code examples wrapped in appropriate formatting.

Exploring Zeek: A Powerful Network Security Monitoring Tool
Zeek is a powerful and flexible network security monitoring tool used by analysts to process and analyze network traffic. It operates by inspecting network packets and generating logs that provide detailed insights into network events. This blog post will guide you through Zeek’s structure, its primary capabilities, and practical use cases.

The Layers of Zeek
Zeek has two main layers:

Event Engine
The Event Engine processes packets, breaking them into smaller components like source and destination addresses, protocol information, session details, and more. This is the foundational layer where data is prepared for deeper analysis.

Policy Script Interpreter
This layer uses Zeek scripts to describe event correlations. It allows analysts to define custom logic for event analysis and automate responses to specific network activities.

Zeek Frameworks
Zeek comes with several extended frameworks to enhance functionality. Some of the key frameworks include:

  • File Analysis: Enables hashing and extraction of files from network traffic.
  • Signature Framework: Detects anomalies based on defined conditions.
  • Intelligence Framework: Processes threat intelligence feeds to identify suspicious activities.

Working with Zeek: Basic Commands

zeekctl status
zeekctl start
zeekctl stop

# Process a pcap file
zeek -C -r sample.pcap

# View saved logs
ls -l /opt/zeek/logs/

Enter fullscreen mode Exit fullscreen mode

Explanation:
-C: Ignore checksum errors.
-r: Read and process a pcap file.

Zeek Signatures: Detecting Anomalies
Zeek’s signature framework allows you to define conditions to detect unusual network behavior. A signature comprises three components: ID, conditions, and actions.

Here’s an example of detecting cleartext password submission:

signature http-password {
    ip-proto == tcp
    dst-port == 80
    payload /.*password.*/
    event "Cleartext Password Found!"
}
Enter fullscreen mode Exit fullscreen mode

To run a signature file:
zeek -C -r sample.pcap -s signature_file.zeek

Image of Docusign

🛠️ Bring your solution into Docusign. Reach over 1.6M customers.

Docusign is now extensible. Overcome challenges with disconnected products and inaccessible data by bringing your solutions into Docusign and publishing to 1.6M customers in the App Center.

Learn more

Top comments (0)

AWS Security LIVE!

Tune in for AWS Security LIVE!

Join AWS Security LIVE! for expert insights and actionable tips to protect your organization and keep security teams prepared.

Learn More

👋 Kindness is contagious

Immerse yourself in a wealth of knowledge with this piece, supported by the inclusive DEV Community—every developer, no matter where they are in their journey, is invited to contribute to our collective wisdom.

A simple “thank you” goes a long way—express your gratitude below in the comments!

Gathering insights enriches our journey on DEV and fortifies our community ties. Did you find this article valuable? Taking a moment to thank the author can have a significant impact.

Okay