5 Chrome VPN Extensions That Leak DNS Data

Chrome VPN Extensions Leaking Data

As any independent internet user, you too have the right to protect yourself against online threats and cyber spying. If recent reports are proof of anything, it is that there are many VPN browser extensions that leak your IP address to third-parties online. This particularly holds true in the case of Chrome VPN extensions. A shocking 70% of the Chrome VPN extensions we tested revealed DNS and data leaks. The very thing you are using to protect yourself online may be exactly the thing harming you.

Is Your Chrome VPN Extension Giving Your Browsing Activity Away?

A well renowned security researcher John Mason, as well as the hacker,  is known as File Descriptor, analyzed 15 VPNs. They found that 10 of the VPNs they tested were leaking data through their browser extensions. According to John Mason, Chrome utilizes a method called DNS Prefetching in order to reduce website loading time. It does so by predicting which websites you might visit in advance.

Connection Settings

Chrome gives its users two options to set up a proxy connection a VPN extension has been installed: fixed_servers and pac_script. Most VPN providers use pac_script mode which gives way for the dynamic HTTPS/SOCKS proxy server host changes. This makes the VPN extension utilize its connection based on user activity. This is a good thing but only up to a certain point.

DNS Prefetching URLs

This means that If you use your VPN Chrome extension to play games, the extension will automatically select the appropriate proxy settings that are best optimized for gameplay. However, this can prove to be particularly tricky since this automatic optimization leaves users more vulnerable to online DNS leaks. To speak in laymen terms, certain websites you visit have DNS Prefetching URLs. This means that your online internet service providers can collect your information regarding websites you frequently visit even if you are using a VPN extension.

There are three particular scenarios responsible for triggering DNS Prefetching.

  1. Manual Prefetching
  2. Omnibox
  3. DNS Prefetching Control

What manual Prefetching and DNS Prefetching control do is allow malicious sources to utilize a custom made web page so that users are forced to leak DNS requests. Omnibox is the URL box that the user types website URLs in. The URLs then suggested by Chrome to users in the Omnibox will be DNS Prefetching. This can give your ISP a chance to use what is called Transparent DNS Proxy which collects the URLs of websites users frequently visit.

Top 5 Chrome VPN Extensions that Leak Your DNS

Like there are good VPNs, there are bad VPNs that you can absolutely not trust to use as extensions while you browse.

  1. Hola VPN
  2. TunnelBear
  3. Betternet
  4. Ivacy VPN
  5. DotVPN

Top 5 Chrome VPN Extensions that Don’t Leak Your DNS

Since we have mentioned the VPNs you cannot trust, we have to mention the VPNs you can most rely on to use as Chrome extensions.

Testing Your VPN for DNS Leaks

If you are doubtful about your security, as is your right, you can always test your VPN for DNS leaks. You can run the following DNS leak test on your VPN. Just follow the simple steps.

  1. Activate your VPN extension in Chrome
  2. Visit Chrome://net-internals/#dns
  3. Select “Clear host cache”
  4. Visit any website of your choosing to check DNS leak vulnerability

Can A Free VPN Chrome Extension Be Trusted?

Most free VPNs out there also have paid subscriptions available for users to choose from. It is natural that most users will want the free version over the paid ones. This is precisely the time to think about the difference between the two plans, why is one free and the other not? While paid subscription plans are self-sufficient in terms of the VPN providers paying for the servers utilized, a free VPN does not have that financial backing. This means they have to generate there revenue somehow. They do this by selling user data. If you think that a free VPN browser extension is the way to go, we have news for you our friends! You are in more danger online than you might think.

Protecting Yourself Against DNS Leak

It is normal to want to know this. There are a few simple steps to follow.

  1. Type Chrome://settings/ in Chrome address bar and hit enter
  2. When the Search Settings open, search for Predict
  3. From here, you will be able to disable both of her autocomplete omnibox setting as well as the prediction service setting


This is all you have to do to ensure your safety online while using a VPN extension. It is not difficult to be safe if you are aware of exactly what is going on in your device while you browse. It is better to be safe than sorry.