Re: TR: Mapping Class A network ( any easy trick?)

From: James Riden (j.riden_at_massey.ac.nz)
Date: 02/22/05

  • Next message: Steve Fletcher: "RE: Bypassing NTFS ACL" 
    To: Vicente Feito <vicente.feito@gmail.com>
Date: Tue, 22 Feb 2005 16:05:00 +1300

    Vicente Feito <vicente.feito@gmail.com> writes:

    > I keep reading the same mistake over and over, not talking about this
    > particular message, but about something most admins do, they start flooding
    > the network with nmap and trying to do a broadcast scan, that's insane, they
    > do nmap -sS -p1-65535 x.x.x.x/24 or something like that, I don't mean to
    > critizice, but I'm my opinion, what I do if I need something like this, is
    > first, just find out what hosts are up, something like nmap -sP <whatever>

    I believe that nmap does ping before doing the SYN scan by default, so
    it won't generate thousands of SYNs for hosts which aren't up.

    -P0 Do not try to ping hosts at all before scanning them.
           [snip]
           By default, Nmap sends an ICMP echo request and a TCP ACK packet to
           port 80. 

    -- 
James Riden / j.riden@massey.ac.nz / Systems Security Engineer
GPG public key available at: http://www.massey.ac.nz/~jriden/
This post does not necessarily represent the views of my employer.
  • Next message: Steve Fletcher: "RE: Bypassing NTFS ACL"

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