Perform a Network Vulnerability Scan with OpenVAS

Objective

Learn how to perform a comprehensive network vulnerability scan using OpenVAS (Open Vulnerability Assessment System) to identify security weaknesses in a target environment.

Purpose

OpenVAS is a powerful vulnerability scanning tool used to:

• Identify misconfigurations, outdated software, and security flaws.
• Generate detailed reports for remediation.
• Simulate real-world attacks to enhance network security.

Tools Required

• Kali Linux (or another Linux distribution with OpenVAS installed).
• Target systems (physical or virtual machines) for scanning.

Lab Topology

• Kali Linux: Running OpenVAS.
• Target Systems: Devices or virtual machines within your network.

Note: Ensure you have explicit permission to scan the target systems.

Walkthrough

Task 1: Installing OpenVAS

1. Update the System:

   sudo apt update && sudo apt upgrade -y
   

2. Install OpenVAS:

   sudo apt install openvas -y
   

3. Initialize OpenVAS:

   sudo gvm-setup
   

   • This command downloads and configures the necessary components.
   • The process may take several minutes.
4. Start OpenVAS Services:

   sudo gvm-start
   

5. Access the Web Interface:
   • Open a web browser and navigate to:

     https://<kali_ip>:9392
     

   • Replace <kali_ip> with the IP address of your Kali Linux machine.
   • Log in with the default credentials:
     • Username: admin
     • Password: Generated during the setup (shown in the terminal).

Task 2: Configuring OpenVAS

1. Update Feeds:
   • Once logged in, navigate to Administration > Feed Status.
   • Ensure all feeds (e.g., SCAP and CERT) are up-to-date.
   • If not, click Update Feeds.
2. Create a Scan Target:
   • Go to Configuration > Targets.
   • Click New Target.
   • Provide the following details:
     • Name: Enter a descriptive name (e.g., “Internal Network”).
     • Hosts: Specify the target IP or range (e.g., 192.168.1.0/24).
     • Port List: Use the default or customize as needed.
   • Save the target.

Task 3: Creating and Running a Vulnerability Scan

1. Create a New Task:
   • Navigate to Scans > Tasks.
   • Click New Task.
   • Fill in the details:
     • Name: Enter a descriptive name (e.g., “Vulnerability Scan”).
     • Scan Targets: Select the target you created earlier.
     • Scan Config: Use “Full and Fast” for a comprehensive scan.
   • Save the task.
2. Start the Scan:
   • Select the task from the list.
   • Click the Start Scan button.
3. Monitor the Progress:
   • Go to Scans > Running Scans to view the scan status.
   • Wait for the scan to complete (this may take time depending on the target size).

Task 4: Reviewing Scan Results

1. Access Scan Results:
   • Navigate to Scans > Reports.
   • Click on the completed scan to view the details.
2. Analyze Vulnerabilities:
   • Review the severity levels:
     • High: Critical vulnerabilities requiring immediate action.
     • Medium: Moderate issues that should be addressed.
     • Low: Informational or minor issues.
3. Export the Report:
   • Click Download Report.
   • Choose the desired format (e.g., PDF, HTML, or XML).
4. Plan Remediation:
   • Use the report to prioritize fixes for high and medium-severity vulnerabilities.

Task 5: Best Practices for Using OpenVAS

1. Update Regularly:
   • Ensure OpenVAS feeds are up-to-date to detect the latest vulnerabilities.
2. Use Credentialed Scans:
   • Configure credentials for better insights into system vulnerabilities.
3. Scan in a Controlled Environment:
   • Avoid scanning production systems without prior authorization.
4. Document and Track:
   • Keep a record of scan results and remediation progress.

Key Takeaways

1. OpenVAS is a comprehensive vulnerability scanning tool suitable for identifying and addressing security weaknesses.
2. Configuring targets and tasks properly ensures accurate and actionable results.
3. Regular scans and feed updates are essential for maintaining network security.

Troubleshooting Tips

1. Web Interface Not Accessible:
   • Ensure OpenVAS services are running:

     sudo gvm-check-setup
     

2. Login Issues:
   • Reset the admin password:

     sudo gvmd --user=admin --new-password=<new_password>
     

3. Scan Failures:
   • Verify network connectivity between the scanner and target systems.
   • Check for firewall rules blocking the scan.

By completing this lab, you’ve gained hands-on experience with OpenVAS, a key tool for vulnerability management and assessment.