RE: Crashing services with NMAP and/or SuperScan ?
From: Jerry Shenk (jshenk_at_decommunications.com)
To: <Petr.Kazil@eap.nl>, <firstname.lastname@example.org> Date: Wed, 24 Nov 2004 07:58:33 -0500
Keying on your last paragraph, I have run into this and did exactly
that. I said something like, "We really need to track down exactly what
broke, can we schedule a time for a repeat test."
From: Petr.Kazil@eap.nl [mailto:Petr.Kazil@eap.nl]
Sent: Tuesday, November 23, 2004 5:42 AM
Subject: Crashing services with NMAP and/or SuperScan ?
> (Side question: Has anyone ever crashed a server when the dangerous
> are disabled?)
I'm doing a series of quickscans in divisions of a large organization. I
intentionally don't go deep, I just scratch the surface. So we can find
only bad security errors, nothing subtle.
One step in the quickscan is a portscan of the internal network. I've
both nmap and Superscan. This usually brings out a lot of unexpected
services, ftp servers, low services, web management interfaces etc.
With Superscan I seem to have blown out a switch. It went "red" on the
Openview screen and didn't react to ping anymore. All the network
continued - fortunately :-) As of today the admins haven't been able to
tell me what really happened. I haven't dared to try Superscan anymore -
although I like it's output very much - especially it's checks for
and anonymous FTP and SMTP.
Yesterday I ran nmap -sS -sV -O ... There were no problems on Win2K and
Unix machines, but on WinNT SP5 (!) machines I seem to have blown out :
- one Oracle TNS Listener - however the admin said "everything continued
- 2 or 3 Storageworks EVA Secure Path services.
Fortunately the admins were not upset. They looked through the services
the servers, looked which ones had gone "stopped" and set them back to
Do you think that running nmap without the -sV -O options could avoid
and still give me enough information?
These are always difficult situations - replications is not easy (I
ask : "Can I run the scan again and see if the same thing hapens?"). I
can't test all OS versions on my test network. I'm not even sure if I'm
really to blame, it could even be coincidence ...
Of course I asked (and re-asked) before my scan: What subnetwork can I
and which IP's should I avoid? Answer: We don't expect any problems,
take our whole subnet.
Your comments are very welcome.
Greetings, Petr Kazil