Sguil (pronounced as ‘squill’) is a robust Network Security Monitoring tool that enables security analysts to gain insights on what is happening on a network in real time.
Sguil is not just an IDS console. Sguil is designed for investigation, information correlation, and incident response.
It does not just display IDS alerts. It integrates IDS alerts, session data, and packets.
How to Use Sguil: A Complete Beginner-to-Practical Guide
Sguil (often pronounced “squill”) is a powerful Network Security Monitoring (NSM) console designed to give security analysts a real-time view of what is happening inside a network.
Unlike a simple IDS dashboard, Sguil is built for investigation, correlation, and incident response.
It does not just show alerts.
It connects alerts, session data, and raw packets into one place.
This blog explains:
- What Sguil is
- How Sguil works
- How to set it up
- How to use it in real investigations
- Why it is still relevant today
What Is Sguil?
Sguil is an open-source network security monitoring tool that acts as a central console for:
- IDS alerts (Snort / Suricata)
- Network session data
- Full packet capture
- Analyst investigation workflows
It was designed by NSM (Network Security Monitoring) practitioners, not just developers.
Its purpose is simple:
Turn raw network data into actionable security intelligence.
How Sguil Works (Architecture Overview)
Sguil itself does not detect attacks.
It collects, correlates, and displays data from other tools.
Typical Sguil stack:
- Snort / Suricata → generates IDS alerts
- Barnyard2 → sends alerts to Sguil database
- SANCP / Zeek → provides session and flow data
- tcpdump → stores packet captures
- MySQL / PostgreSQL → backend database
- Sguil client → analyst console
Sguil connects all of these so when an alert fires, you can instantly:
✔ See the session
✔ See related traffic
✔ Pull the actual packets
✔ Investigate in one place
Typical Use Cases of Sguil
- Intrusion detection analysis
- Malware traffic investigation
- Incident response
- Threat hunting
- Network forensics
- SOC alert triage
Sguil is widely used in:
- SOC environments
- University cyber labs
- Blue-team training
- Government and enterprise NSM setups
Installing Sguil (High-Level Overview)
Most modern users deploy Sguil through Security Onion, which bundles:
- Sguil
- Suricata
- Zeek
- Elasticsearch
- Full packet capture
- Dashboards
Option 1: Install via Security Onion (Recommended)
- Fastest setup
- Fully integrated
- Best for learning and labs
Option 2: Manual Installation
Requires configuring:
- IDS engine
- Database
- Sguil server
- Sensors
- Client
Because manual install is complex, most teams use Security Onion.
Understanding the Sguil Interface
When you open Sguil, you usually see:
Event Console
Main alert dashboard. Shows:
- Timestamp
- Source IP
- Destination IP
- Signature
- Priority
- Status
This is where analysts spend most time.
Session View
Shows network conversations related to an alert:
- Protocol
- Duration
- Bytes transferred
- Direction
Helps you see:
- Was this a scan, download, beacon, or exploit?
Packet Capture Panel
Allows you to extract full packets and open them in Wireshark.
This is where real investigation happens.
Real-Time Alerts
Live feed of new events.
How to Use Sguil in Real Security Work
Let’s walk through a realistic workflow.
Step 1: Monitor Alerts
Start in the Event Console.
You’ll see alerts like:
- Possible malware download
- Port scan
- Exploit attempt
- Command-and-control traffic
Your job:
- Filter noise
- Prioritize real threats
You can:
- Filter by IP
- Filter by signature
- Filter by severity
Step 2: Classify the Alert
Right-click an alert and mark it as:
- Real threat
- False positive
- Escalated
- Investigating
This builds your investigation history.
Step 3: Analyze the Session
Open the session data.
Check:
- Duration
- Repetition
- External destinations
- Unusual ports
- Data size
Ask:
- Is this beaconing?
- Is this data exfiltration?
- Is this malware download?
Step 4: Pull Packet Capture
Extract the PCAP file.
Open in Wireshark.
Look for:
- Payloads
- URLs
- File downloads
- DNS queries
- C2 patterns
This confirms whether the alert is real.
Step 5: Correlate Activity
Search Sguil for:
- Same source IP
- Same destination
- Same signature
This helps you answer:
- Is this isolated?
- Or part of a larger attack?
Step 6: Escalate or Close
If malicious:
- Create incident report
- Alert IR team
- Block IPs
- Isolate host
If false positive:
- Close event
- Tune IDS rule
Example Investigation Scenario
Alert:
“Possible Malicious HTTP Download”
Steps:
- View alert
- Check session: large outbound transfer
- Pull PCAP
- Inspect file in Wireshark
- See suspicious executable
- Correlate DNS logs
- Confirm malware infection
- Escalate incident
Sguil ties all of this into one investigation space.
Why Sguil Is Still Valuable
Even today, Sguil remains powerful because:
✔ It supports deep analysis
✔ It is analyst-focused
✔ It handles full packet context
✔ It trains real investigation thinking
✔ It teaches true blue-team workflows
It doesn’t just show graphs.
It shows evidence.
Limitations of Sguil
- Old-style interface
- Steep learning curve
- Manual setup complexity
- Not cloud-native
- Requires NSM knowledge
This is why many teams use it:
- inside Security Onion
- in SOC labs
- for education and training
Who Should Learn Sguil?
- SOC analysts
- Blue teamers
- Threat hunters
- Cybersecurity students
- Incident responders
- Network defenders
If you want to truly understand how attacks look on a network — Sguil is gold.
Progress becomes powerful when you stop waiting for perfect conditions and start working with what you have!!
K
“You don’t find clarity by escaping uncertainty — you find it by learning how to walk through it!!” – K
यदा अनुशासनस्य चयनं सुखस्य चयनात् कठिनतरं भवति, तदा एव इच्छितं जीवनं निर्मीयते!!
K
