[CentOS] Paranoid Firewalling
ethericalzen at gmail.com
Tue Sep 6 21:04:34 UTC 2005
Kirk Bocek wrote:
> Scot L. Harris wrote:
>> Actually this won't reduce any bandwidth to your server. The probes
>> still hit that address, you are just blocking those packets in iptables
>> from begin able to get any further.
> Are you saying that the single connect-and-drop that this scheme
> introduces is going to use the same bandwidth as a brute-force password
> attack on hundreds of login names?
Question, because I am not sure. Wouldn't the script that is being
run have to be intelligent enough to move to the next machine
without exhausting its attempts at guessing passwords in order for
your firewalling scheme to effectively reduce bandwidth?
What I mean is, the script attempts to connect and try a password.
It doesn't get a response so it assumes that the machine simply
returned a login denied and tries again. It may try this several
times per username (depending on the script). If that's the case, as
it's not actually bothering to keep track of success of connection
you're getting the same amount of connects as previously. Is that
Now granted the above scenario is assuming a truly brain dead
script, but they aren't all that more sophisticated than that (some
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