OpenVAS

Overview

OpenVAS (Open Vulnerability Assessment System) was initiated by Greenbone Networks in 2008, headquartered in Germany. It is the world's largest open source security vulnerability scanner. The project is built on the GVM (Greenbone Vulnerability Management) framework, managing over 100,000 NVT (Network Vulnerability Test) cases covering operating systems, network devices, web applications, databases, and more.

OpenVAS is a core tool for security practitioners in penetration testing and compliance assessment. The Community Edition is fully open source and free, while the enterprise product Greenbone Security Manager (GSM) offers commercial deployment with enhanced management. OpenVAS integrates seamlessly with the information gathering, vulnerability validation, and exploitation phases of the penetration testing basics, forming a key link in the security assessment pipeline.

Key Strengths

• Massive Vulnerability Coverage: 100,000+ NVT test cases covering CVE, CWE, and other mainstream vulnerability standards, continuously updated by the community. Most commercial scanners do not match OpenVAS in raw rule count.
• Open Source and Free: The Community Edition requires no license fees, ideal for budget-constrained security teams and individual researchers. Combined with Nmap and Metasploit, it builds a fully free penetration testing environment at 0 cost.
• Flexible GVM Framework: GVM supports scheduled scan tasks, SMTP alerts, customizable report templates, target group management, and 3 scheduling strategies for quarterly compliance scanning.
• Active Ecosystem & Integration: The Greenbone community regularly publishes rule updates, and OSP (Open Scanner Protocol) allows 2 third-party scanners such as Nessus and Nmap to be integrated for multi-engine detection.

Product Ecosystem

Greenbone Vulnerability Management (GVM)

GVM is the core management framework of OpenVAS, consisting of three main components: gvmd (management daemon), openvasd (scanning daemon), and GSAd (web interface daemon). It provides a complete scan lifecycle from target definition, task scheduling, scan execution, to report generation and remediation tracking.

Greenbone Security Manager (GSM)

GSM is Greenbone's commercial hardware/virtual appliance, adding a centralized management console, role-based access control, SLA reports, multi-tenancy support, and commercial support on top of the Community Edition, suitable for compliance audit scenarios.

Open Scanner Protocol (OSP)

OSP is Greenbone's open scanner protocol that allows third-party scanners such as Nessus and Nmap to be integrated into the GVM framework for unified management and multi-engine collaborative scanning.

Limitations

• Outdated Web Interface: The Greenbone Security Assistant (GSA) web interface is comprehensive but lacks modern UX design, visualization dashboards, and alert analysis compared with commercial products such as Nexpose or Qualys.
• Steep Installation Requirements: Full deployment involves PostgreSQL database configuration, NVT feed synchronization, and certificate management, requiring Linux administration skills. Docker or pre-built VM images are recommended to lower the barrier.
• Unpredictable Feed Updates: NVT rule updates depend on community contributions and Greenbone's release cadence. Response to critical 0-day vulnerabilities is slower than commercial vulnerability management platforms.

Use Cases

• Security Audit & Compliance (★★★★★): GVM's scheduled scanning and report templates match periodic vulnerability scanning requirements for ISO 27001, PCI DSS, and other standards.
• Penetration Testing Workflow (★★★★★): Integration with Metasploit and Nmap covers the complete penetration testing chain from information gathering to exploitation.
• Budget-Conscious Small Teams (★★★★★): A fully functional, free vulnerability scanning solution to establish basic security detection at zero cost.
• Education & Research (★★★★): Suitable for university cybersecurity courses and CTF training environments to learn vulnerability identification and assessment.
• Large Enterprise Production (★★): Evaluate GSM commercial edition or enterprise platforms such as Qualys and Nessus for better SLA and technical support.

Pricing

The Community Edition VM image is available from the OpenVAS official GitHub; the GSM commercial edition is available through Greenbone official channels.

FAQ

• What is the difference between OpenVAS and Nessus? OpenVAS is open source with 100K+ NVT rules and free to use; Nessus is a commercial product with better usability, UI design, and enterprise support. Both can be used together for broader vulnerability coverage.vulnerability scanner comparison
• Is OpenVAS suitable for production environments? Yes for small to medium environments. The scanning engine is stable and reliable, but for large-scale deployments consider GSM commercial edition or evaluate enterprise solutions such as Qualys and Nessus.
• How do I update the OpenVAS NVT feed? Run greenbone-nvt-sync manually or configure a cron job for automatic updates. The Community Edition should sync at least once a week.vulnerability scanning and CVE lifecycle
• Does OpenVAS support Windows? The server runs on Linux only, but it can be managed remotely via the web interface; scanning clients support Windows targets. Windows users should use Docker deployment or pre-built VM images.Docker deployment for beginners
• Will OpenVAS scanning affect production services? Validate scan strategies in a test environment first. Some active detection plugins may impact fragile systems; configure scan windows and rate limiting to minimize risk.server operation and maintenance tips