nessus-adduser - add a user in the nessusd userbase

nessus-adduser

The Nessus Security Scanner comes with its own user base which contains the list of who can use the services of nessusd, and what restriction (or rules) each user has.

nessus-adduser is a simple program which will add a user in the proper nessusd configuration files, and will send a signal to nessusd if it is running to notify it of the changes.

The program is straightforward and asks for the following items:

• Login

the login name of the nessusd user to add

• Password

the password that the user will use to connect to nessusd

• Authentification type

the authentification method the client will use. The recommended method is “cipher”. However, if you compiled nessusd without the cipher support or if you are using a Nessus client which does not support the cipher layer, you'll have to use “plaintext”

• Rules

the set of rules to apply to the user. See below.

Each user has his own set of rules. Rules are here to restrict the rights of the users. For instance, you can add user “joe” so that he can only test the host “192.168.1.1”, whereas you can add user “bob” so that he can test whatever IP address he wishes.

Each rule fits on one line. A user can have an unlimited amount of rules (and can even have no rule at all).

The syntax is: accept|deny ip/mask and default accept|deny

Where mask is the CIDR netmask of the rule.

The default statement must be the last rule and defines the policy of the user.

The following rule set will allow the user to test 192.168.1.0/24, 192.168.3.0/24 and 172.22.0.0/16, but nothing else: accept 192.168.1.0/24

accept 192.168.3.0/24

accept 172.22.0.0/16

default deny

The following rule set will allow the user to test whatever he wants, except the network 192.168.1.0/24: deny 192.168.1.0/24

default accept

The keyword client_ip has been defined, and is replaced at run time by the IP address of the nessusd user. For instance, if you want your users to be able to only be able to scan the system they come from, then you want them to have the following ruleset: accept client_ip

default deny

nessus-rmuser(8), nessusd(8), nessus(1)

The canonical places where you will find more information about the Nessus project are: http://www.nessus.org/ (Official site)

http://cvs.nessus.org (Developers site)

nessus-adduser was quickly written by Renaud Deraison <deraison@cvs.nessus.org>

nessus-adduser creates temporary files in $TMPDIR/. If this variable is not set, then it will use /var/tmp which may be a security risk depending of your configuration.

If you set your TMPDIR variable to /tmp, then you are in trouble.