How To Use The Free ClamAV Linux Antivirus Software Package

ClamTK Graphical Linux Antivirus
ClamTK Graphical Linux Antivirus.

The most common problem that my friends face when using their Windows based computers involves malware, viruses and trojans.

I read a great article during the week which shows just how easy it is to install Malware on your computer and not from some shady website (the equivalent of a dark alley) but from a mainstream download site (the equivalent of a major high street store).

Linux is considered by many people to be more secure than Windows and it has led to some people declaring that it isn't possible to get viruses, trojans or malware within Linux.

I have never actually come across any nasties whilst running Linux but that isn't to say that it isn't possible and won't happen.

As the risk for contracting viruses on Linux is relatively low many people don't bother with antivirus software.

If you are going to use Antivirus software it doesn't seem logical to spend loads of money on a commercial package and that is where ClamAV comes in.

Here are 3 good reasons for using ClamAV:

  1. You have sensitive data on your computer and you want to lock down your machine as much as possible and make sure that nothing can affect your computer or your data.
  2. You dual boot with Windows. You can use ClamAV to scan all of the partitions and all of the drives on your computer.
  3. You want to create a system rescue CD, DVD or USB which can be used to troubleshoot for viruses on a friend's Windows based computer.

By using a system rescue USB drive with an antivirus package installed you can search for viruses without actually having to boot into Windows.

This prevents the viruses having any effect whilst trying to clear them.

ClamAV isn't 100% accurate, in fact no Antivirus package is, with even the best coming in at around the 80% mark.

Many antivirrus software providers produce a free bootable rescue DVD which you can use to troubleshoot your computer without logging into Windows.

ClamAV has the added advantage of being able to scan Linux drives as well.

ClamAV isn't necessarily the best virus scanner available on the market but it is free and fairly accurate.

The ClamAV Wikipedia page has details of how effective it is.

When I ran ClamAV against my Windows partition it found 6 false positives. The files it found were from my mobile broadband software and AVG.

In this guide I am going to show you how to install ClamAV and how to use the graphical tool ClamTK to manage it.

The trouble with ClamAV is that it is command line only and so for the average person it might be a bit complicated.

Fortunately there is a tool called ClamTK which provides a nice and simple graphical front end to ClamAV.

You will find ClamTK within the package managers of most distributions. For instance Ubuntu users will find it in the Software Centre and openSUSE users will find it within Yast.

Use the graphical desktop for your distribution to locate and run the ClamTK package.

For instance to load ClamTK in Ubuntu open up the Dash and search for ClamTK. Within Xubuntu, click on the menu icon in the top left corner and enter ClamTK into the search box.

The process is slightly different depending on the desktop environment and distribution but I am sure you all know how to navigate the desktop that you have chosen.

When ClamTK appears click on the icon.

The main application is split into four sections:

  • Configuration
  • History
  • Updates
  • Analysis

The configuration section is used to set up how you want ClamAV to run.

The history section lets you see the results of previous scans.

The updates section enables you to import new virus definitions.

Finally the analysis section is how you start the scans.

 Before you can scan for viruses you need to load in up-to-date virus definitions.

Click on the "Updates" link and then click on "OK" to check for updates.

You will then be able to download new virus definitions

ClamAV has settings which lets you customise how it runs. For instance when you choose a folder to scan you might just want to scan that one folder and not the sub folders or you might want to scan very large files which obviously take longer to process.

In order to change the settings click on the settings icon.

By hovering over each checkbox you will be able to see a tooltip which explains what the option is for.

The first four checkboxes lets you scan for password checkers, large files, hidden files and scan folders recursively.

The other two checkboxes updates and toggles how the icons work within the application. (I.E. do you have to click them once or twice).

To scan for viruses click on either the scan a file icon or scan a folder icon.

I recommend choosing the scan a folder icon. You will be shown a browse dialog box. Choose the drive you wish to scan (i.e. the Windows drive) and click OK.

ClamAV will now search recursively through the folders (depending on the switch within the settings screen) looking for bad things.