Back to the main page

Nessus - vulnerability scanner

The Nessus is scanner that tries to discover and warn of vulnerability on scanned system.
It's using plugins, which are actually scripts that do vulnerability checks. A plugin can be developed using NASL - Nessus Attack Scripting language.
Once scanning is over, a result can be reported, say like HTML file.

This is example of working with Nessus on Solaris. Get the Solaris package from

It comes as datastream, so first translate it to a package.
> pkgtrans Nessus-4.2.2-solaris-sparc.pkg .

Then install it.
> pkgadd -d . TNBLnessus

Installation will advise next things to be done:
NOTE: you may need to add additional library path:
>setenv LD_LIBRARY_PATH /opt/nessus/lib:${LD_LIBRARY_PATH}

Okay, so let's add a user who can login to Nessu engine and perform scans
> /opt/nessus/sbin/nessus-adduser
Login : nessus
Login password :
Login password (again) :
Do you want this user to be a Nessus 'admin' user ? (can upload plugins, etc...) (y/n) [n]:
User rules
nessusd has a rules system which allows you to restrict the hosts that nessus has the right to test. 
For instance, you may want him to be able to scan his own host only.

Please see the nessus-adduser manual for the rules syntax

Enter the rules for this user, and enter a BLANK LINE once you are done :
(the user can have an empty rules set)
		<-------------- press ENTER, no rules, so user can scan any IP range !! 

Login             : nessus
Password         : ***********
Rules             :
Is that ok ? (y/n) [y]
User added

The Nessus has to be registered in order to be used. This is free for home use. Register and get activation code from Nessus web site.

Once you have registration code (format as in next command), go and register nessus.
>/opt/nessus/bin/nessus-fetch --register 1234-AAAA-BBBB-CCCC-0000
Your activation code has been registered properly - thank you.
Now fetching the newest plugin set from
Your Nessus installation is now up-to-date.
If auto_update is set to 'yes' in nessusd.conf, Nessus will update the plugins by itself.

Finally start Nessus
> /etc/init.d/nessusd start

> pgrep -l nes
 6505 nessusd
 6504 nessus-service

To use it (with web browser), connect to https://nessus-server:8834/

Once there, first create a policy for scanning.

Then define host you want to scan and launch scan.

Say that scanning of one host takes 10 min, monitor the progress.

Once scanning is done, a report can be downloaded with selecting format, like HTML.

Back to the main page