RE: Scanning OpenBSD with NMAP - mysterious Results ???

["Joseph W. Shaw II" <mrman@darkside.org>]

On Thu, 31 May 2001, John Verne wrote:

> > NMAP says : Difficulty 25374 (Worthly Challenge)
> 
> Ok, so you are doing a port scan and a fingerprint of the remote OS.  nmap
> is reporting that it thinks it can figure out by querying the TCP/IP stack.
> 
> This is not a measure of "security", but more a way of finding out what
> "others" can find out about you.  The right kind of information could be
> used against you (by matching vulnerabilities against your OS).

TCP sequence number predictability most certainly is a measure of an
operating system's security.  The harder they are to predict, the
better off you are from spoofing attacks.  Just ask Shimomura.  However,
anything pre-2.9 is sub-par for the new method of TCP sequence
predictability.  I'm unsure if the latest nmap now supports the new
method.

Regards,
--
Joseph