OpenVAS - Open Vulnerability Assessment System

OpenVAS, short for Open Vulnerability Assessment System, is a popular open-source vulnerability scanner that helps network administrators and security professionals identify and remediate security vulnerabilities in their IT infrastructure.

OpenVAS was initially created as a fork of the now-defunct Nessus vulnerability scanner, which was the de facto industry standard for vulnerability scanning in the early 2000s. Nessus was later converted to a closed-source, commercial product, which prompted the creation of the OpenVAS project as a free, open-source alternative.

OpenVAS consists of several components, including a central management server, multiple scanning engines, and a web-based user interface. 

• The central management server is responsible for coordinating the scanning engines and providing a centralized interface for managing scans and viewing results. 
• The scanning engines perform the actual vulnerability scanning.
• The web-based user interface allows users to configure scans, view reports, and manage the system.

One of the main advantages of OpenVAS is its flexibility and extensibility. It supports a wide range of operating systems, including Linux, Windows, and macOS, and can scan a variety of network devices, including routers, switches, and firewalls. Additionally, OpenVAS can be customized and extended through the use of plugins, which can be developed by the user community or purchased from third-party vendors.

OpenVAS scans can be configured to detect a wide range of vulnerabilities, including software misconfigurations, missing patches, and weak passwords. The scanner also has the ability to identify misconfigured network services and protocols, such as open SMTP or DNS servers, and can perform authenticated scans to detect vulnerabilities in the underlying operating system.

Once a scan is completed, OpenVAS generates a detailed report that lists all identified vulnerabilities, along with severity ratings and recommendations for remediation. The report can be exported in a variety of formats, including PDF and HTML, and can be used to prioritize remediation efforts and demonstrate compliance with industry regulations and best practices.

In conclusion, OpenVAS is a powerful and flexible open-source vulnerability scanner that can help network administrators and security professionals identify and remediate security vulnerabilities in their IT infrastructure. Its ability to support a wide range of operating systems and devices, as well as its extensibility through plugins, makes it a valuable tool in the security professional's toolkit.