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From: Josh Paetzel <josh@tcbug.org>
To: "Charles Ulrich" <charles@idealso.com>
Date: Wed, 1 Dec 2004 12:04:10 +0000
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cc: questions@freebsd.org
Subject: Re: blacklisting failed ssh attempts
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On Wednesday 01 December 2004 17:41, you wrote:
> This morning I noticed that an attacker spent over a full hour
> trying to brute-force accounts and passwords via ssh on one of our
> machines. These kinds of attacks are becoming more frequent.
>
> I was wondering: does anyone know of a way to blacklist a certain
> IP (ideally, just for a certain time period) after a certain number
> of failed login attempts via ssh? I could change the port that sshd
> listens on, but I'd rather find a better solution, one that isn't
> just another layer of obscurity.
>
> Thanks!

This may or may not help you, but I generally firewall ssh so that 
only known addresses can get in.  (whitelisting as opposed to 
blacklisting)

-- 
Thanks,

Josh Paetzel