Firewall Audit

[paul at pauldotcom.com (Paul Asadoorian)]

Chris Bentley wrote:
> Paul/Ron any idea what type of scans I could run using nmap or nessus.
> Also this would make a good technical segment for the show.

Great question!  See below for answers that are just off the top of my head:

1) nmap -sT -n -T4 -p1-65535 <targets behind the firewall>

That will take some time, but the connect() scan works better for
firewalls and causes them not to crash/fill up state table.  Always scan
all ports, and you can also mess around with different source ports too.

2) nmap -sU -n -T4 -p1-65535 <targets behind the firewall>

Don't forget UDP!

3) Nessus is a vulnerability scanner, but does contain a really sweet
TCP and UDP port scanner.  I'd recommend running it against all ports
using select plugin families.  This way you can also find any
vulnerabilities in your firewall (making certain that the actual IP
address of your firewall is included in the targets) and the systems
behind it.  Also, there are several plugins that test "firewall stuff",
515 to be exact:

# find . -name '*.nasl' -print0 | xargs -0 grep -i firewall | wc -l
     515

:)

Cheers,
Paul


-- 
Paul Asadoorian
PaulDotCom Enterprises
Web: http://pauldotcom.com
Phone: 401.829.9552