Struggling With the Calendar Code - Turns out we need to work all weekend on fixing bugs before the customer will even consider accepting our system for production use. I got assigned a tick...
Nessus is available on Windows and Linux based systems. It is purportedly the most popular vuln scanner. It can scan for a number of things such as remove control and access, misconfiguration, bad passwords, and Denial of Service exploits. The tool can help you prepare for a security audit.
You write tests for Nessus to perform. The tests are written in a custom scripting language called NASL. You can subscript to receive tests from Tenable. The program output can be formatted in text, HTML, or even XML formats. A free competitor in the vuln scanning space is OpenVAS.