Tag Archives: scanner


I continue to publish some my coding.

Hostcheck is a simple Perl script that can be useful to quickly check if a list of host is up.
It just read a host file and check if the host are available doing a ping test or trying to open a socket.

Nothing great, but it may help to quickly check that most of things are right after a network change, for instance.
Because we want to test many hosts, and not to scan, the pace is fast so it may not be 100% reliable. The idea is to see roughly is the connectivity is correct or if your whole LAN is down.
It uses colors and is easy to read, so it might be good to show to your manager ! :)

I hope it will be useful. More info and download link are there.

Nessus 4.2

Nessus 4.2 is out.

I tried it out and I must say that the new UI is great. I am not a big fan of Flash and I regret this choice. However, the design is excellent, all options are accessible in a logical way. Instead of spreading over the options like it used to be, they come to you in the right order.

I also appreciate that the server and the client set-up are now unified thanks to the web interface (you can access it from localhost or from the network indifferently).

The report section has also been greatly improved.

So, if you were already an Nessus user, it is worth upgrading.

Talking about the set-up, there is an up-to-date package for openSUSE (of course, there are a lot less dependencies than before).

Prads – a new passive scanner !

Edward Bjarte Fjellskål contacted me to let me know about a new program he, Kacper Wysocki and Jan Henning Thorsen made, called Prads.

Prads is a fingerprinting scanner, coded in Perl. I am fond of this kind of tool, so I enjoyed checking it out.

Prads operates differently from Nmap or SinFP that I already introduced on this blog. It works passively, meaning that it aims to scan systems without sending out a single packet. It does this by capturing the traffic silently though an interface in promiscuous mode.
The advantage, of course, is that it is much more stealth than a classic scanner, which leaves usually a lot of log entries in firewalls or IDS.
It works on several layers and is based on all the common protocols, that should make it efficient and fast : TCP, UDP, ICMP, ARP.

Using Prads is very simple, just look at prads –help for more info.

There is a sample output, after running it a few seconds on my network :

% sudo perl prads.pl -d eth0 --os --service
Starting prads.pl...
Using eth0
DBD::SQLite::db prepare failed: table asset already exists(1) at dbdimp.c line 271 at prads.pl line 320.
 1243801518 [SYN       ] ip: - Linux - 2.6 (newer, 7) [S4:64:1:60:M1460,S,T,N,W7:.] distance:0 link:"ethernet/modem"
 1243801518 [SYNACK    ] ip: - Linux - 2.6 (newer, 0) [5792:64:1:60:M1460,S,T,N,W0:ZA] distance:0 link:"ethernet/modem"
; 3.0.10-1.1.1 Firefox [] distance:1 link:SERVICE
 1243801518 [SERVICE   ] ip: - Unknown HTTP - HTTP;  [] distance:1 link:SERVICE
; 3.0.10-1.1.1 Firefox [] distance:1 link:SERVICE
; 3.0.10-1.1.1 Firefox [] distance:1 link:SERVICE
; 3.0.10-1.1.1 Firefox [] distance:1 link:SERVICE
; 3.0.10-1.1.1 Firefox [] distance:1 link:SERVICE
 1243801536 [SYNACK    ] ip: - Linux - 2.6 (newer, 5) [5792:64:1:60:M1380,S,T,N,W5:ZA] distance:7 link:"GPRS, T1, FreeS/WAN"
 1243801536 [SERVICE   ] ip: - Generic TLS 1.0 SSL - ;  [] distance:1 link:SERVICE
 1243801438 [UDP       ] ip: - @Linux - 2.6 [20:64:1:.:2:0] distance:0 link:ethernet [OLD]
 1243801438 [UDP       ] ip: - @Linux - 2.6 [20:64:1:.:2:0] distance:2 link:ethernet [OLD]
 1243801544 [SERVICE   ] ip: - - - DNS; - [] distance:1 link:SERVICE
 1243801549 [SYNACK    ] ip: - Cisco - 7200, Catalyst 3500, etc [4096:255:0:44:M1460:A] distance:0 link:"ethernet/modem"
 1243801549 [SERVICE   ] ip: - Cisco SSH - Protocol 1.5; 1.25 [] distance:1 link:SERVICE
 1243801549 [SERVICE   ] ip: - OpenSSH - Protocol 1.5; 5.1 [] distance:1 link:SERVICE
 1243801600 [SYN       ] ip: - Linux - 2.6 (newer, 7) [S4:64:1:60:M1460,S,T,N,W7:.] distance:0 link:"ethernet/modem"  [OLD]
 1243802459 [SYNACK    ] ip: - UNKNOWN - UNKNOWN [8192:128:1:60:M1460,N,W8,S,T:A] distance:0 link:"ethernet/modem"
 1243802459 [SERVICE   ] ip: - Windows SMB - ;  [] distance:1 link:SERVICE
 1243802459 [SERVICE   ] ip: - Windows SMB - ;  [] distance:1 link:SERVICE
 1243801596 [SYNACK    ] ip: - Linux - 2.6 (newer, 5) [5792:64:1:60:M1380,S,T,N,W5:ZA] distance:7 link:"GPRS, T1, FreeS/WAN"  [OLD]
 1243801596 [SERVICE   ] ip: - Generic TLS 1.0 SSL - ;  [] distance:1 link:SERVICE [OLD]
 1243801367 [UDP       ] ip: - @Windows - MS [20:128:0:.:0:0] distance:0 link:ethernet [OLD]

As you can see, there is already some interesting output.
It detected quite well my Linux laptop running Firefox (UPDATE : according to the author, it is a bug as client detection has not been implemented yet) and surfing a few website, the provider’s DNS servers, another Linux machine and a Windows desktop. Concerning the last two, I guess that a more completed signature database would have allowed a more precise fingerprinting. The Linux box is a wifi Linksys router and the Windows one runs Vista.
Also, the gateway curiously did not show up itself, but the presence of a SSH connection helped to find it.
Finally, there is a little incoherence between the distance shown for the DNS server (=2, correct) and for the service (=1).

To be honnest, so far, I had never found interest in the existing passive scanners. There were POf but it is now pretty outdated and seems not to be developped anymore. Ettercap could fingerprint the system seen while sniffing (profiles), but it was definitely too limited and not really furtive. Moreover, Nmap with the right options, or SinFP itself can be quite stealth.

But now Prads has a place among the tools I use. It is efficient, straight forward and provide some useful info, beyond the OS detection : service and client info, distance, etc. It is nice because, once again, all these data are obtained withou sending out any request at all.

As it is in its early stage, it is very promising and I am looking forward to Prads and its signature database improving. Please keep up the good job !

That’s all for today. This tour was short but I will write again about this tool, as I will be using it. The next post will probably introduce the way the signature database is built and how it can be extended. So keep wired and don’t forget to check the Prads homepage.

SinFP, part II : comparison with Nmap 4.20

Here is the update of my previous test of SinFP.

I compared then the output of SinFP and Nmap on different machines, and found out that SinFP made a slightly better job than Nmap in OS detection, though it is not the primary goal of Nmap whereas it is the one of SinFP.

However, I made a mistake that the author of SinFP made me aware of.

I conducted the tests of Nmap using the package of my distribution, thinking it was the latest one.

Actually, it was only the version 4.10. Moreover, the current version, 4.20, brought up a new OS detection engine.

Therefore, a new test with version 4.20 was absolutely needed.

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