Domain Fronting can be used as a tool to bypass censorship by ISPs and governments. Domain Fronting can also be used by hackers to obtain the information they want from you. What is domain fronting? This article explains domain fronting in brief and lets you decide if it is good or bad by explaining both the advantage and dangers of domain fronting.
Domain Fronting explained
Domain fronting, in short, is changing the destination of an internet connection midway using encryption. If you want to browse a restricted website, you can use one of the following methods to reach it:
- Domain Fronting
The problem is that many governments are banning or restricting VPN and TOR traffic on different ISP networks. ISPs have specific orders from such governments to ban one or more website of any nature. Earlier, eight to ten years ago, we could easily use a proxy and reach the restricted website. Technology changed, and now it is easier than ever to detect traffic that is using a proxy. Not only that, but TOR (The Onion Router) can also be cracked now with some military grade techniques. Those two are no more viable methods to access restricted websites.
Thus, we are left with VPN and Domain Fronting. In an attempt to censor and to keep an eye on what its citizens are doing, many countries are banning/restricting VPNs too. They do not want encrypted traffic so that they know what is going on. The ISPs cannot rebel against the government of any country that restricts or bans VPN. They have to oblige.
The last method to access a restricted website is to apply domain fronting. You, as a user, cannot apply domain fronting though. You have to use an app that employs domain fronting. One such app is Telegram – the chatting app banned by Russia and many more countries.
These apps have built-in algorithms that allow users to access restricted websites or websites banned in that particular country where the user is located. This is done by altering the code in the header in the host websites. For invigilators, it generally shows that it is connecting to an innocent website, probably without HTTPS too. In the middle of the handshake between the website and app, the app first establishes an encrypted connection (could be as simple as HTTPS) and then switches route to another website. That website may be a banned or restricted website.
Thus, it is possible to cheat the invigilators at ISP and government levels to contact a restricted website while the Internet police think you are connected to some other website when all the time you were communicating with the banned website.
Domain Fronting can be used to circumvent any type of censorship. That’s the good part. The next section talks about the dangers of domain fronting.
Dangers of Domain Fronting
While domain fronting is being used to let users access restricted websites and services, there is a good chance that hackers might use the same technique to mislead users and mine the data they want.
Both the namesake domain and the restricted website (or infected website, in case of hackers) are hosted on the same set of servers. When one tries to connect to the namesake domain, its header sends another GET request that gives it the address of the restricted website. Now, this could be a simply restricted-by-government website or a computer infected by hackers.
Depending upon who is using domain fronting, it is both advantageous and dangerous. While mostly, private messaging apps were using the technique, both Google and Amazon dumped Telegram saying they are against their Terms and Conditions. Currently, Telegram is looking for other cloud service that would provide them with the ability of domain fronting.
There are several other cases where the use of domain fronting was genuine – to allow free speech. But it seems the world governments are closing all routes to freedom of expression. In the same breath, we can say domain fronting has its own dangers because if it can replace destination, it may lead you to fake sites, and you won’t ever know.
Now read: What is a Cold Boot Attack?