Welcome back!
We’ve just seen what a great tool Tor is. It’s used by people all over the world to browse the Web
freely, anonymously and circumvent censorship while online surveillance becomes more and more prevalent.
It can be used to browse both the surface web and the deep dark web.
One of the first questions many users ask is if using Tor or browsing the Dark Web is illegal.
The simple answer is that nor using Tor neither browsing the Dark Web is illegal. Tor is just an
open network that anonymizes its users and the onion services that run on the dark web are only applications
like web, chat or email servers.
But most of the activities that occurred on the Dark Web are illegal.
Note that there are some countries like China or iran that block the Tor network, by blocking
the communication with the Tor relays which are public.
So the subject of the legality or illegality of the Dark Web, in those countries of the world, is an ongoing
discussion.
Keep in mind that there is no such thing as 100 % security.
And even Tor has some vulnerabilities. In this lecture
I'll show you a few things so you can use it securely.
For example by putting the entire Tor circuit together, an adversary could be able to see the IP
address of the user on the first relay and the final destination of their web traffic on the last relay,
allowing him to match users to their online activity.
Some reports showed that the many exit relays are compromised.
FBI, Europol and NSA used this attack to shut down hundreds of Dark Web domains and the arrest
tens of criminals.
If you want to dig deeper into this attack, you should read its analyses done by the Tor project.
I’ll also attach it as a resource to this lecture.
Let's see what are the best practices when using Tor so that you don't expose yourself to vulnerabilities
and exploits that could compromise your identity, privacy or your device.
In my opinion, one of the biggest problems with Tor is the traffic isolation, which means sensitive
traffic that is transmitted outside to the Tor network.
Just imagine that using Tor you download a document that contains the link you'll click on. That link
will be opened with your default browser, which is not Tor and your
real identity will be exposed. Or a document could embed a script that automatically accesses a server
and you are exposed.
So you should use Tor in an isolated, security focused system,
that runs on a dedicated machine or in a VM.
The TAILS Linux, distro we’ve talked about in a previous lecture,
is a very good candidate because all traffic goes only though the tor network.
There are no other applications that you'll connect normally to the Internet to expose your real IP
address.
So installing and running the Tor browser on Windows is not the smartest decision if you take
anonymity seriously.
If you want to check if Tor is working and that your connections are really anonymized, you can visit
this website that will tell you if you appear to be coming through the Tor network.
In this example, I am not using Tor and the website displays the correct message.
Let's try it with Tor!
I'm opening the Tor browser and I'll paste this address in the url bar.
This is Tor and I'm pasting the address.
Congratulations, this browser is configured to use Tor. Perfect.
The exit relay is located in Luxembourg.
A second rule is that you should not open documents downloaded through the Tor browser while you are
online.
Open them while you are off line or from an operating system like TAILS.
As I've just said, they can contain resources that could reveal your IP address.
Similarly, do not use torrents over Tor.
They will send out your real IP address in the tracker GET request and deanonymouse you.
Do not sign in to websites if you don't want them to find out who you are.
Once you sign into a website like Facebook, you have identified yourself to that website and to anyone
who might be observing the activity on that site.
Use only HTTPS and other protocols that are encrypted.
Do not use HTTP.
Tor will encrypt the traffic to anonymize you, but the exit relay
will have access to the original packet.
If it’s not encrypted like say an HTTP packet, then the exit relay can see sensitive data like
usernames and passwords.
Take a look at this diagram made by the Electronic Frontier Foundation to get a better understanding.
Do not visit the Dark Web or visit only sites you trust. The Dark Web is the criminal's heaven.
Many sites will try to infect you with malware.
Do not click on ads or random links.
Changed the security level of the Tor browser to safer or safest.
So go to options -
Privacy and security -
and there you'll find 3 security levels: standard, which is the default, safer and safest.
Note that it’s possible that some websites won’t work because components like JS or
HTML5 media will be blocked.
Use the latest version of the Tor browser because security flaws are often discovered and patched.
For example, in June 2019, a critical security flaw that has helped cyber criminals to
take full control of systems running vulnerable versions was discovered.
Also, note that the Secret Services all over the world monitoring the Tor network for illegal activities.
Even if you are just visiting the Dark Web
you can become a suspect or even a target.
OK.
That's all!
Follow all of these advice for a secure and anonymous web browsing experience.