Scan your LAN for unauthorized IPs

diff <(nmap -sP 192.168.1.0/24 | grep ^Host | sed 's/.appears to be up.//g' | sed 's/Host //g') auth.hosts | sed 's/[0-9][a-z,A-Z][0-9]$//' | sed 's/</UNAUTHORIZED IP -/g'
populate the auth.hosts file with a list of IP addresses that are authorized to be in use and when you run this command it will return the addresses that are pingable and not in the authorized list. Can be combined with the "Command line Twitter" command to tweet unauthorized access.
Sample Output
UNAUTHORIZED IP - 192.168.1.69

1
By: bandit36
2009-03-12 05:28:08

What Others Think

Running it shows: "diff: auth.hosts: No such file or directory". So I must give it a thumbs down.
plasticdoc · 486 weeks and 4 days ago
That's because "auth.hosts" is a text file listing all the authorized IP addresses on the network. Please see the description in white.
bandit36 · 486 weeks and 4 days ago
Is there anyway to do this with mac addresses? I have populated the auth.hosts file with all of the authorized mac addresses on my network, but not quite sure what I would need to change to make it work.
etsorbme8 · 486 weeks and 2 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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