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From: Jason Opperisano <opie@817west.com>
To: netfilter@lists.netfilter.org
Subject: Re: use of the limiting options
Date: Wed, 26 Jan 2005 11:17:27 -0500	[thread overview]
Message-ID: <20050126161727.GA6583@bender.817west.com> (raw)
In-Reply-To: <Pine.LNX.4.53.0501251248340.24829@altaica>

On Tue, Jan 25, 2005 at 12:54:54PM -0600, Tib wrote:
> 
> I'd like to use the --limit and --limit-burst options to protect my sshd
> from dictionary password attacks. Considering the userbase and activity
> level I'd say that something like this would suit me just fine.
> 
> --limit 6/hour
> --limit-burst 2
> 
> This would limit it to two connect/login attempts at first, and then one
> more every 10 minutes.. correct?
> 
> Would this be the proper command to use? I'm trying to just limit
> connections from the outside world, not from the local network, hence the
> address as a destination:
> 
> iptables -A INPUT --d 66.80.174.210 --dport 22   \
>    --limit 6/hour --limit-burst 2

that's a fantastic way to DoS yourself.  so after 8 idiots try to
connect to your SSH server--you're locked out from connecting yourself
for an hour...*brilliant*.

try some real security measures instead of snake oil:

- disable password auth on your SSHD and only allow public key auth

- filter access to your SSHD by source IP, if possible

- use some sort of VPN access (IPSec/OpenVPN/etc) to get to your SSHD,
  and only allow access that way.

-j

--
"Please do not offer my god a peanut"
        --The Simpsons


  parent reply	other threads:[~2005-01-26 16:17 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-01-25 18:54 use of the limiting options Tib
2005-01-25 19:08 ` Tib
2005-01-25 19:28   ` Tib
     [not found]     ` <294d5daa0501251137328fa4ff@mail.gmail.com>
     [not found]       ` <Pine.LNX.4.53.0501251340370.24829@altaica>
2005-01-25 19:51         ` Mark Moseley
2005-01-25 19:56           ` Tib
2005-01-25 20:17             ` Mark Moseley
2005-01-25 20:22               ` Tib
2005-01-26  7:58                 ` Tib
2005-01-26 18:43                   ` Mark Moseley
2005-01-28 21:32                     ` Tib
     [not found]                     ` <7096989.1107132520756.JavaMail.rct@kale>
2005-01-31 19:00                       ` Bob Tellefson
2005-01-26 16:17 ` Jason Opperisano [this message]
2005-01-28 21:29   ` Tib
2005-01-31  3:44 ` Josh Nerius
2005-01-31  5:52   ` R. DuFresne
2005-03-02 10:33   ` forwarding internet connection elg3ne
2005-03-02 10:41     ` Essien Ita Essien
2005-03-02 12:34     ` Jörg Harmuth

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