Server Hardening, What is it really?
Server Hardening is often misunderstood as being a one off process to tighten the security on a server before it becomes live on the Internet. This is only partially correct, sure you want to tighten the security of your server before putting it on a Public Network, but its not enough to put it in and forget about it. The idea behind server hardening is the process of securing the machine not only before it goes live, but permanently.
We have seen around the Internet, “Server Hardening Guides”, “Security Checklists” and “Hardening Protocols” all of which seem to be one off documents where you follow through the checklists ticking off the boxes and completing the required steps. Once all the steps have been completed, email the completed checklist to the boss stating the machine is now secure and that’s the end of that.
This is actually good practise as an initial process, but what happens in the future when someone creates a utility that can breach the security of your hosted server? Or someone finds that your running an out of date software application that can be exploited? The sad fact about the internet is that if a server can be compromised your pretty much guaranteed that it will be in time.
The idea behind server hardening is to make your machine secure and keep it secure and up to date as possible.
What steps can you take? Well the main things are keep your software up to date, most software developers release fixes, updates or patches which rectify found flaws or exploits, remove unused usernames and logins from your servers, disable SSH access with the root account, make sure you are behind a firewall, use a data integrity / change detection tool like Tripwire and most importantly take backups lots of backups. Regular audits on your servers for software updates is also a good habit to get into. Another good habit to get into is keeping documentation on your hosted servers this way you can see what versions of software you have installed, when patches or updates were installed, who performed the work etc etc.
Did we mention backups? Regular checked backups are very important, especially when the data on your server is critical.
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