Blocking Spyware Using the HOSTS File

When considering manual system defense against internet threats, most of the users come to the question of using the HOSTS file for increased anti-spyware protection, sooner or later. However, the problem of apparent complexity involved when using it sometimes turns away even those interested in protecting their systems manually.

However, it’s not as hard as it might seem, and this tutorial in using the HOSTS file for anti-spyware defense needs will illustrate the actual simplicity of this task.

What is a HOSTS file?

Simply put, the HOSTS file caches all the IP addresses of the websites you visit for increased internet connectivity and speed, as these addresses are kept in the HOSTS file, which is actually checked before your system queries the DNS servers.

For example, you have the BBC website cached in your HOSTS file: its entry would be displayed as 212.58.224.131 www.bbc.co.uk. Therefore, it would be easily reachable and it would load faster than websites that are not cached in your HOSTS file.

That said you could make a list of trusted and most visited websites in this file for increased loading speed.

OR, you could BLOCK unwanted sites by using the same HOSTS file and adding these websites and changing their IP addresses to that of your own computer.

Where is the HOSTS file located?

Windows NT/2K/XP = [System root]\System32\Drivers\Etc
Windows 95/98/ME = [Drive]\Windows
The [drive] is usually drive "C:"
The [System root] is usually "C:\WinNT" or "C:\Windows"

How is the HOSTS related to spyware?

Most malware and spyware parasites hijack your HOSTS file in order to redirect you to malicious websites by changing the IP addresses of legitimate ones to websites of intruder’s choosing.

Blocking undesirable sites with HOSTS file

However, the abovementioned process may be reversed, as you can use the same tactics to redirect any possible malicious sites to another site in order to prevent infection. Instead of opening a malicious site, your web browser will show a “Page not found” error. To block an undesirable site in your HOSTS file, do the following:

·        Locate the HOSTS file

·        Right-click the file, select Open With…

·        Select Notepad from the program list

·        Press OK

·        Enter the address of a website you wish to block (e.g. www.bbc.co.uk)

·        Enter 127.0.0.1 in the IP field

·        Save the HOSTS file

Congratulations! You are now able to block undesirable sites with the HOSTS file.

Does blocking malicious sites offer the ultimate protection against spyware?

No. Although a well-edited HOSTS file does offer increased passive anti-spyware protection, the sheer amount of malicious websites is just way too large. You’ll have to constantly update your HOSTS file with hundreds of new addresses if you want this method to offer complete protection.

Moreover, not every malware parasite hijacks the hosts file or uses site redirection to cause harm. Some are known to tamper with the registry, while others operate via backdoors. There are a myriad ways for spyware to damage your system, and using the HOSTS file for malicious purposes is just one of them.

We recommend using the latest versions of spyware removers in conjunction with edited HOSTS file for maximum anti-spyware protection.