This guide by linuxbsdos will help you get familiar with the pkg audit command available on PC-BSD and FreeBSD.
Pkg is that package manager and one of the its many commands I think you should get to know asap is the audit command. It’s used to audit installed packages against known vulnerabilities. I could be wrong, but I don’t think your favorite Linux distribution’s package manager has an equivalent command.
The command is very simple. Just pass the -F flag to pkg audit and it will output installed packages with outstanding vulnerabilities. By running pkg audit -F on a fresh installation of PC-BSD 10.1 KDE, for example, it reported the following vulnerable packages.