Robert Moskowitz wrote:
Rudi Ahlers wrote:
lucian@lastdot.org wrote:
On Tue, 22 Jul 2008 16:34:54 +0200 Rudi Ahlers Rudi@SoftDux.com wrote:
Bowie Bailey wrote:
Bo Lynch wrote:
just wanted to get some feedback from the community. Over the last few days I have noticed my web server and email box have attempted to ssh'd to using weird names like admin,appuser,nobody,etc.... None of these are valid users. I know that I can block sshd all together with iptables but that will not work for us. I did a little research on google and found programs like sshguard and sshdfilter. Just wanted to know if anyone had any experience with anything like these programs or have any other advice. I really appreciate it.
The simplest thing is to change the port. I know it's "security through obscurity", but it works well and can be used along with whatever other security enhancements you care to use.
By changing the ports on all our servers to a high (above 1024) port, we have eliminated SSH scans altogether - been running like that for a few years now without any problems.
I also add a small script in /etc/profile to email me when someone logs in via SSH, since only a few privileged ppl should use SSH altogether
Interesting idea with this script thing. Can you provide more details or the script? _______________________________________________
Yea, it's simple :)
echo 'SSH (localhost.localdomain) on:' `date` `who` | mail -s "Alert: Access from `who | cut -d"(" -f2 | cut -d")" -f1`" xxxxx@yyy.com
OK. A chance to learn some more for me.
Is there a 'best' placement for this script in /etc/profile? Is localhost.localdomain a placeholder here for foo.bar.com?
I put stuff like that right at the end, and localhost.localdomain is basically the server's name, from where I copied this script, so replace that with my.linux.server.com - or whatever