Date: Tue, 23 Jun 2009 09:53:43 +0800 From: TJ Varghese <tj@tjvarghese.com> To: Benjamin Lee <ben@b1c1l1.com> Cc: freebsd-questions@freebsd.org Subject: Re: Best practices for securing SSH server Message-ID: <c7f2adc20906221853o617deb2bg17141566c9e13a8d@mail.gmail.com> In-Reply-To: <4A403324.6090300@b1c1l1.com> References: <b6c05a470906221816l4001b92cu82270632440ee8a@mail.gmail.com> <4A403324.6090300@b1c1l1.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, Jun 23, 2009 at 9:43 AM, Benjamin Lee<ben@b1c1l1.com> wrote: > On 06/22/2009 06:16 PM, Daniel Underwood wrote: >> On a BSD box at work (at an extremely fast connection and static IP), >> I run an SSH server. =A0I am the only person who uses the server, but I >> use it from some locations that are behind a dynamic IP (so I can't >> set pf rules to filter by IP). =A0I will always, however, use the same >> laptop to connect to the server. =A0Due to the speed and location of the >> connection, it's a relatively high-risk target. >> >> What are some good practices for securing this SSH server. =A0Is using a >> stored key safer than a password in this instance? I have no >> experience with port-knocking, but I'd appreciate some tips or >> suggested beginning references... I welcome any and all advice. >> >> Note: I do require X11 forwarding (not sure whether that's relevant info= rmation) > > I have password authentication disabled on my public SSH server. =A0You > can accomplish this by setting: > > ChallengeResponseAuthentication no > > in /etc/ssh/sshd_config. =A0See sshd_config(5) for more information. > > This allows you to enforce the use of stronger authentication methods > (e.g. public key). =A0Keep in mind, however, that this setup will only be > secure if you keep your alternate credentials (e.g. private key) secure > as well. > > If for some reason you would prefer to use password authentication, I > would recommend that you look into automatic brute force detection. > There are a number of utilities in ports available for this purpose, > including security/sshguard and security/denyhosts. I'd recommend changing the listening port to something other than 22. This reduces brute-forcing attempts by script-kiddie tools. Public key authentication should be mandatory, in addition to having a passphrase to your private key. Make sure your laptop is secure. Stay on top of the security lists for openssh vulnerabilities.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?c7f2adc20906221853o617deb2bg17141566c9e13a8d>