What is GNU IceCat?

GNU IceCat is the GNU version of the Firefox browser. The main advantage of IceCat is an ethical one because it is free software. Firefox by Mozilla distributes non-free software as plug-ins and addons. The Tor browser, built on Firefox, is potentially harmful to your freedom.

Why IceCat?

The Tor browser bundle is extremely vulnerable. We have seen time and time again that users are identified. There are numerous examples of users being identified through JavaScript powered malware. IceCat is a good alternative for the Tor browser in my opinion.

Installing

$ yaourt -S icecat

Arch and Manjaro package manager yaourt greatly simplifies the installation of IceCat. Some distributions will require that you build IceCat from source. This is beyond the scope of this blog post. You can also pull a copy from the gnu ftp. Remember to get the latest version.

Setup

Setup is a breeze.

SSH into your Tor box. You aren’t running Tor locally are you? Watch my video on Tor. Done? Good. Now go build a VPS and install Tor on that. Once you have Tor installed we can connect.

$ ssh -L 9050:127.0.0.1:9050 user@1.1.1.1

We want to expose port 9050 to ourselves on localhost from our VPS.

Now open IceCat and choose the following privacy settings on launch.

1. Disable JavaScript
2. Do not load custom fonts
3. Tracking protection
4. Isolate requests to First Party domains
5. Spoof Referers (sic)
6. Block third-party requests

Make sure that Enable Geolocation and Enable WebGL are disabled.

It will look like this -

Now open Preferences->General->Network Proxy

Let’s setup a manual proxy configuration by choosing that option. Then fill out the SOCKS Host box with 127.0.0.1 and port 9050. Check mark the Proxy DNS when using SOCKS v5.

It will look like this -

Test It All!

1. Go here in your new secure Tor Browser. It should report a Congratulations message.

2. Try the following command in a terminal.

$ curl --socks5 localhost:9050 --socks5-hostname localhost:9050 -s https://check.torproject.org/ | cat | grep -m 1 Congratulations | xargs

You should see text that states ‘Congratulations. This browser is configured to use Tor.’ You can now be confident that data sent over port 9050 when connected to your VPS will go through the Tor network.

Am I an elite invisible hacker who can never be caught now?

No.

Threats?

Absolutely. Even css can be a potential vulnerability. Turning off JavaScript will remove a wide array of threats but html and css can still potentially be a method by which a browser attack can be executed. Don’t forget to implement firejail and apparmor in combination with other necessary behavior modifications depending on your threat matrix.