Gentoo Archives: gentoo-user

From: Brian Davis <bridavis@×××××××.net>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] OpenSSH security
Date: Tue, 07 Nov 2006 20:09:55
Message-Id: 4550E6DE.9070803@comcast.net
In Reply to: Re: [gentoo-user] OpenSSH security by fire-eyes
1 In addition to fail2ban, look at deny2hosts and sshdfilter.
2
3 fire-eyes wrote:
4 > James Colby wrote:
5 >
6 >> List members -
7 >>
8 >> I am running OpenSSH on my home gentoo server. I was examining the
9 >> log files for OpenSSH and I noticed multiple login attempts from the
10 >> same IP address but with different user names. Is there a simple way
11 >> that I can block an IP address from attempting to log in after
12 >> something like 3 failed login attempts?
13 >>
14 >> My Gentoo box is connected to a linksys router connected to my cable
15 >> modem, the linksys is doing port forwarding to my gentoo box. Also, I
16 >> would like to avoid limiting which IP addresses can log into my SSH
17 >> server
18 >>
19 >> Thanks for any ideas,
20 >> James
21 >>
22 >
23 >
24 > What you're seeing is a common, automated dictionary style attack. There
25 > are several ways to get rid of them.
26 >
27 > The simplest way is to install fail2ban and it will create firewall rules.
28 >
29 > The next less-simple way is to change the port sshd listens on. The
30 > scripts assume the default of 22.
31 >
32 > The best way is to change the port sshd listens on, and also move to key
33 > based authentication, and disable password based authentication. In this
34 > way, even if they got the port, got a real user name, and had the right
35 > password, it would not matter -- They haven't got the key.
36 >
37 --
38 gentoo-user@g.o mailing list

Replies

Subject Author
Re: [gentoo-user] OpenSSH security Pavel Sanda <ps@××××××××××.cz>
Re: [gentoo-user] OpenSSH security Mick <michaelkintzios@×××××.com>