Sguil

Author: Kustas Kurval

Cyber Security Engineering C11

Written 06.06.2016

Introduction

This tutorial was made to make an introduction to Sguil. Sguil (pronounced sgweel) is built by network security analysts for network security analysts. It is a collection of free software components for Network Security Monitoring (NSM) and event driven analysis of IDS alerts. Sguil's main component is an intuitive GUI that provides access to realtime events, session data, and raw packet captures. Sguil facilitates the practice of Network Security Monitoring and event driven analysis.

The Sguil client is written in tcl / tk and can be run on any operating system that supports tcl / tk (including Linux, *BSD, Solaris, MacOS, and Win32).

It is provided by Q Public License

Sguil integrates alert data from Snort, session data from SANCP, and full content data from a second instance of Snort running in packet logger mode.

In this introduction I will be covering Sguil in Xbuntu. You will need to know basic Linux syntax and terminology also some terminology concerning overall intrusion detection and prevention systems (IDPS) and overall basic networking.

Software architecture

A sguil system is composed of a single sguil server and an arbitrary number of sguil network sensors. The sensors perform all the security monitoring tasks and feed information back to the server on a regular basis. The server coordinates this information, stores it in a database and communicates with sguil clients running on administrators' desktop machines. It can also issue requests for specific information from the sensors.

Each sensor monitors a single network link (although you can have multiple sensors on one physical machine). They collect several different types of information:

1. Snort monitors the link for security events, and logs them to a file on the local disk.
2. Barnyard takes events from the snort log file and sends them to the sensor agent, which inserts them into database running on the sguil server in near real-time
3. A separate instance of snort logs the full content of all network packets to the local disk (this typically requires a large separate data partition)
4. SANCP records TCP/IP sessions and forwards them to the database on the sguil server
5. The sguil agent also listens for commands from the sguil server. These commands are typically requests for packet data previously logged by Snort.

Tools that usually make up Sguil

Tool	Purpose
MySQL 4.x or 5.x	Data storage and retrieval
Snort 2.x / Suricata	Intrusion detection alerts, scan detection, packet logging
Barnyard / Barnyard2	Decodes IDS alerts and sends them to sguil
SANCP	TCP/IP session records
Tcpflow	Extract an ASCII dump of a given TCP session
p0f	Operating system fingerprinting
tcpdump	Extracts individual sessions from packet logs
Wireshark	Packet analysis tool (used to be called Ethereal)

Contents

Since Sguil is dependant on many other types of software to gather, facilitate, store ,decode and analyze I will be using Xbuntu based distribution Security Onion which saves massive amount of time to set up the entire environment.

See also

• Sagan
• Intrusion detection system (IDS)
• Intrusion prevention system (IPS)
• Network intrusion detection system (NIDS)
• Metasploit Project
• nmap

References

• Sguil Homepage
• Sguil FAQ
• NSMWiki: The official wiki for the Sguil project.