Nessus gives you the ability to configure your scan based on different scan and policy templates.
Ports can be defined in ranges or individually, with valid ports ranging from 1 to 65535. Once all the steps are complete, Nessus runs each host against a database of known vulnerabilities in an attempt to discover which host contains which vulnerabilities. The steps that are followed during scanning are:
Identify which software components are vulnerable to attacks (FTP, SSH, SMB and more).Identify which operating systems and services are running on which ports.For instance, a plugin could be launched and targeted at a host to: Nessus performs its scans by utilizing plugins, which run against each host on the network in order to identify vulnerabilities. Cost Effective for Companies of All Sizes.Advanced Detection Means More Protection.
Other advantages and features of the professional version include:
You can download current version of Nessus in here. Nessus works by testing each port on a computer, determining what service it is running, and then testing this service to make sure there are no vulnerabilities in it that could be used by a hacker to carry out a malicious attack. Nessus is a tool that checks computers to find vulnerabilities that hackers COULD exploit. In fact, Nessus is one of the many vulnerability scanners used during vulnerability assessments and penetration testing engagements, including malicious attacks. Nessus is an open-source network vulnerability scanner that uses the Common Vulnerabilities and Exposures architecture for easy cross-linking between compliant security tools. Tenable also contains what was previously known as Nessus Cloud, which used to be Tenable’s Software-as-a-Service solution. Tenable.io is a subscription-based service. Nessus is a proprietary vulnerability scanner developed by Tenable, Inc.