One important thing to know when using a computer system is that it is prone to attacks. This could be either locally (when a computer system is used by more than one person) or remotely (when used to connect to the internet). It is true for a computer with any operating system. So though most of the points that would be discussed applies to any operating system, some are particularly applicable to a Linux system.
For a variety of reasons Linux is built with security consciousness than many alternatives out there. But this doesn’t mean that a Linux box can’t be compromised.
#1: Learn to use file and directory permissions.
File permission is an integral part of Linux. The basic idea of this is that every user of a Linux system have their unique restrictions on the files (and directories) that they have access to. If anybody creates a file(s) he/she determines who is qualify to access or modify such files. So if one is not authorized to access a particular file, he is locked out from those particular files. So you need to be careful in assigning permissions to users who share a computer system with you because you’d be giving them a very powerful privilege. Learn how to use file permissions on Linux.
#2: Use Secure Password.
This is a very important aspect in securing your system. It is common for people to use passwords that are word that are familiar them. And also to use one particular password across different platform – for familiarity and easy remembrance. This is very dangerous. As if your password is compromised in one platform, it could be used to get access to other of your platforms. For instance, if your Facebook account is hacked, your computer could be hacked using the same password (assuming you’re one of those people that use one password across different accounts). Try as much as possible not to use password that could easily be guessed or broken using a password-cracking software. A combination of alphabets, numerals and symbols. For example, ‘#193r1@’ or ‘N193r1@’ is a more secured password than ‘Nigeria’ – you get the idea. Another thing I want to emphasize here is that you try to carry your passwords on your head, don’t ever write them down. Even if you have to write them down, not in one place and let it be inconspicuous. DON’T write something like; ‘PASSWORD: oranges’.
#3: Leave the ‘root’ Alone.
The root user is the most powerful user on a Linux system, also referred to as the system administrator. The root user always have access to every part of the system. It is very advisable to not use your system as the root user. First this is to protect you from yourself, like entering a command that can wipe your entire system or cause damage to your system. Secondly, it helps to promote others to carry out deadly attack on your system if the root account of your computer system is hacked – the hacker could remotely enter deadly commands to compromise your system. One way to do this is to create and alternate user account for daily usage and only invoke the power of the ‘root’ ONLY when necessary. And there is also the ‘sudo’ command in many Linux distribution (distro) that could confer temporary root powers to you without you being the root user.
#4: Back-Up Your Computer Regularly.
This is a practice most computer users take for granted, and realize how important when their computers get compromised or corrupted. It simply involves saving important files on your computer somewhere else – outside your computer. There are some few cloud/internet based files storage services (Google Drive, Dropbox etc.) that could offer few gigabytes of storage space here and there that you could use. But because of internet cost and maximum security reasons, a personal external hard disks would be better. And try as much as possible not to put all your files in one location – anything can happen – I hope you remember the eggs and the basket story. If you have not gotten an external hard disk, it is highly advisable for you to do so – two 250GB hard disks would be nice for an average user. And always put copies of your files into these hard disks, so that even if your system is compromised (from malwares, spywares, or the likes) you could easily do a clean re-install and then copy back your files.
#5: Encrypt your files.
Encrypt is a security measure that involves you making your files are digitally locked and unreadable with only you having the key to open it. So even when your system is compromised and your files copied by an intruder the file(s) would looked gibberish to him/her. There are many software that could help you to encrypt files on your computer system. Among them is Truecrypt – so you could download and test it out.
#6: Keep Linux Up-To-Date.
Regularly up dating your Linux system is a good way of ensure that latest bug and security fixes are available to your system. This would make your system less security vulnerable. You would be keeping intruders on their toes as they try as much as possible to find ways of locating vulnerabilities in your operating system. It would be like somebody chiseling the outer wall of your fence while you are adding concrete to the inner part. There are many GUI tools bundled with every Linux distro you could use to update you system with just a few clicks.
I think if these points are put into practice, coupled with a security-conscious mindset, they’d go a long way in giving your system a basic security defense it definitely needs in these highly digital interconnected world.