Block .Onion Sites Running with Tor Proxy in Firefox Browser

Ton onion proxy is a very popular proxy tool that provides anonymity from within your web browser. In addition, it can also be used to create dynamic web sites set up using the “.onion” top-level domains. The “.onion” sites can only be reached through the Tor proxy networks and therefore are often misused by criminal activities, for example, malware distribution, ransom collection and so on. Tor onion proxy uses a large number of dynamic nodes with encrypted connections that it becomes really difficult to trace the computers that actually are running the “.onion” sites.

Such .onion sites have been recently seen to operate the web pages connected to some of the ransomware malware related links. Since the .onion sites do not need a traditional web host, the security agencies like FBI cannot easily take them down.

To prevent cyber-criminals from using these sites to install malicious software on your PC, you can disable the “.onion” sites altogether in the Firefox browser. Here is how:

1. Launch Firefox web browser, type about:config in the address bar and press Enter.
2. After clicking on the “I’ll be careful, I promise” button, proceed to Firefox advanced settings manager.
3. In the search box type network.dns.blockDotOnion to find the setting we need.
4. Make sure the value of this setting is set to true. If the value is false, then double-click on this setting to switch it back to true.
5. That’s it. Now Firefox will block all sites that operate using the .onion top level domains.

This new setting has been added in the newer versions of Firefox (starting from the version 45.0) so that the users can easily block all the .onion web sites at the DNS level. However, if you use the Tor proxy then you can easily disable this setting and access those .onion sites.