Ensure portaudit and portupgrade are installed:

cd /usr/ports/ports-mgmt/portaudit
make install clean

cd /usr/ports/ports-mgmt/portupgrade
make install clean

rehash

then simply run:

portaudit -a

If you already have portaudit installed, ensure your portaudit database is up to date:

portaudit -Fd

and upgrade affected packages using

portupgrade <package-name>

You might want to ensure your port’s database is up to date before hand using cvsup or portsnap

I would however recommend portsnap over cvsup – see excerpt from portsnap pkg-description file:

Portsnap is a system for securely updating the ports tree by distributing signed compressed snapshots. This is the client half of that system; it downloads compressed snapshots into /usr/local/portsnap (“portsnap fetch”) and uses those to extract a ports tree into /usr/ports (“portsnap extract”) or update an existing tree (“portsnap update”).

In addition to operating entirely over HTTP, portsnap can use under a tenth of the bandwidth required by CVSup if a copy of the ports tree is being updated every few days.

WWW: http://www.daemonology.net/portsnap/

— Colin Percival

To install portsnap (if not already installed):

cd /usr/ports/ports-mgmt/portsnap
make install clean

Then simply run

portsnap fetch update

For further information regarding FreeBSD vulnerability auditing, please see this great post:

http://blogs.techrepublic.com.com/security/?p=477