Security Onion is a comprehensive, open-source Network Security Manager (NSM) platform designed to provide deep visibility and robust security monitoring for network environments.
What Security Onion Does
Security Onion integrates multiple critical security functions into a single, cohesive platform. It is engineered to capture, analyze, and provide context around network traffic and host activities, making it an essential tool for network security monitoring, intrusion detection, and incident response.Key Features and Functionality
Full Packet Capture
Security Onion utilizes tools like `netsniff-ng` to perform full packet capture, recording all network traffic seen by the Security Onion sensors. This feature acts as a detailed recorder of network activities, similar to a video camera, capturing every aspect of the traffic, including exploit payloads, phishing emails, and file exfiltration. This data is stored and managed with built-in mechanisms to purge old data to prevent storage overload.Network-Based and Host-Based Intrusion Detection Systems (NIDS and HIDS)
- NIDS: Security Onion employs rules-driven IDS systems such as Snort and Suricata to identify and alert on known anomalies and malicious traffic patterns.
- HIDS: The platform uses Wazuh as its host agent, which performs log analysis, file integrity checking, rootkit detection, and real-time alerts on endpoints.
Analysis Tools
Security Onion includes several powerful analysis tools to help analysts make sense of the vast amount of data collected:- Sguil: This is the primary analyst console, providing a GUI to view alerts from Snort, Suricata, OSSEC, and Bro. Sguil allows analysts to pivot from alerts to packet captures or full session transcripts, enabling detailed investigation and correlation of traffic.
- Other Tools: Additional tools like Snorby, Squert, and Enterprise Log Search and Archive (ELSA) are available for managing and analyzing alerts and captured events. These tools can export data for further analysis in Network Forensic Analysis Tools (NFAT) such as NetworkMiner, CapME, or Xplico.
Data Management and Visualization
- Alerts and Dashboards: The platform features an alerts panel that serves as a central clearing house for all alerts generated by various subsystems. Dashboards are available for visualizing data, creating graphs and charts from log data, and are fully customizable to fit specific environmental needs.
Scalability and Management
Security Onion can be deployed in various configurations, including standalone setups with a server and sensor, or scaled with a master server and multiple sensors. Management is facilitated through Secure Shell (SSH) and web client remote access, ensuring flexible and secure administration.Additional Capabilities
- Endpoint Logs and Telemetry: Security Onion can collect logs from endpoints and other network equipment, including Windows, Mac OS, and Linux systems, using elastic agents. It also supports OSquery functionality for real-time data retrieval during investigations.
- Threat Hunting and Detection Engineering: The platform supports threat hunting workflows using gathered data and detection engineering techniques to create new alerting rules based on identified malicious or suspicious activities.