As a compromise why not change IP Tables to only allow connections
from the local subnet to SSH on reboot/firstboot ?
i.e. DHCP gets IP address 192.168.1.200 with subnet mask 255.255.255.0
so connections are allowed in from 192.168.1.0/24.
Date: Thu, 19 May 2011 07:18:38 -0600
From: Kevin Fenzi <kevin(a)scrye.com>
Subject: Re: Default Fedora installation suffers from egregious
Content-Type: text/plain; charset="us-ascii"
On Wed, 18 May 2011 17:35:38 -0700
dirk cummings <sexynaya2010(a)hotmail.com> wrote:
On a default install of Fedora 14, and also the latest release
candidate for 15, the user is presented with:
An iptables rule that opens port 22 to the worldsshd service
automatically startedsshd_config with default option: PermitRootLogin
yes It's like every new install comes with the keys to the castle
hanging on outside of the door for anyone who comes knocking.
I find this situation a serious oversight in light of the fact that
Fedora obviously values security (like selinux, or how the installer
forces a minimum password length, etc)
Any experienced linux user will know to check iptables and disable
unnecessary services, but I wouldn't expect this from a new linux
user (exactly the people the refreshed GNOME experience is supposed
to attract). I think the default configuration should be in the name
of security, and sshd should not be listening on a default port with
an open rule with root login enabled.
The reason for this has been headless installs. Ie, if you install via
vnc or the like, and finish the install and reboot and don't have
access to the physical console, ssh is your only way to access the
newly installed machine and setup accounts, etc.
If someone can come up with a solution that covers this case, we could
revisit this, but it's not an case thats easy to fix in any kind of
clean way. ;(
If it's brute force attacks that are the vector of concern, perhaps we
could look at a default hashlimit rule in front of the ssh. (ie, 1
attempt per minute or the like).