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Nessus-alph2 available

Apr 04, 1999, 23:04 (1 Talkback[s])

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                    T h e   N e s s u s   P r o j e c t


Paris, 4th April 1999. I am pleased to announce the availability of
Nessus-alpha2, one year after the release of Nessus-alpha1.

1. What is Nessus ?

        Nessus is a free, easy-to-use and open-sourced remote security 
scanner, distributed under the GPL, such as SATAN. Every security 
check is coded as an external plugin, thus making the product easier
to upgrade / maintain / modify for your needs.
Also, Nessus is made up of a client and a server. The server is in charge
of the attacks, and the client is the frontend which is used to configure
the tests and analyze the results.

        This release (which is called alpha2 and not beta1 or 1.0 because
a lot of features are still to be added) is stable and usable by everyone
-- not just geeks or hackers (in the open-source meaning of the term of

2. What are the new features of Nessus-alpha2 ?

        Nessus has many new features, mainly :

 - Intelligent remote service detection
        Too many security scanners consider that all web servers run
        on port 80, all FTP servers on port 21, and so on, so they
        get quickly confused when facing a host which is running a 
        server on another port (like a web server on port 8080).

        And this is really annoying is not it ? So many holes that
        are left because they were on another port !

        Nessus will attempt to find out which service is running 
        on each port, and will launch its attacks according to the
        result of its findings.

 - Up-to-date vulnerability database
        Nessus features 208 security checks, which may seem not enough
        compared to commercial security scanners, but most of these
        tests are new, that is, they have been published recently.
        So Nessus is up-to-date, and the tests that are not done are
        the older ones (which you must not forget to test, but which
        are becoming rare)

 - Advanced portscanning facilities
        Nessus now performs several port scans, which can be combined to
        get more efficient results.
        The current scan techniques are :
                TCP ACK, FIN, SYN, XMAS, Maimon, FTP bounce scan
                UDP 'icmp unreachable' scan

 - Advanced security between the client and the server
        The Unix client now communicates with the Unix server
        over a ciphered communication layer. 

        Also, the client authentification can now be done
        via a public key exchange, thus securing even more
        the use of the Nessus server

 - Advanced oand documented plugins API
        Nessus now features a complete manual describing how easy it is
        to write your own tests.

        It is now even possible to make a trivial GUI to your plugins,
        thus making them more user-friendly and user-configurable.

        The plugins API features things like plugins dependencies,
        plugins intercommunication, FTP functions and more. Also,
        it solves the eternal problem of the headers to use when
        dealing with raw sockets, structs tcphdr and all the like.

 - More portable
        Whereas Nessus-alpha1 was for Linux only, thanks to many 
        contributors, Nessus-alpha2 now compiles and runs under
        all major BSD flavors, Linux, some flavors of Solaris,
        IRIX and even SCO with some modifications

        It has heavily been tested under FreeBSD 2.2.6 and 3.1,
        Debian GNU/Linux and the Linux RedHat 5.2
 - No limitations (except a moral one)
        Whereas most commercial security scanner limit the range of
        IPs that you can test, Nessus, because it is free, gives you
        the total freedom to do what you want with it. The only 
        limitation I ask you to observe is :

                'Do not test the computers that are not under your
 - Now supports CIDR addresses
        You can now ask to test CIDR-noted addresses, like  (can you imagine I have waited so long
        to implement this one ?)         

 This is among all the other 'standard' features.

3. Where to get it ?

  Before you download Nessus, make sure you have these two sets of 
 libraries installed :
        gmp 2.0.2 : available at
        gtk+      : available at
        (Nessus is compatible with GTK 1.0 to 1.2 included, but incompatible
        with the first versions of GTK 1.1)

 The Nessus package is available here : 


        There are now several clients that can be used with Nessus.
   Note that the above package comes with the standard GTK client.

 + NessusW is a Win32 client written by Noam Rathaus 
   and Aviram Jenik , of the SecuriTeam
   ( It is available at :
 + Net::Nessus is a perl module which handles the communication
 with the server and which has been written by 
 Jochen Wiedmann . It is available at
  ... and the various CPAN mirrors.
 + NessusJ is a Java client written by Alexis de Bernis a new version
 of which is to be released soon. 
4. The Nessus project web resources

  The project home page :       
  The developement page :
  The mailing list page :