Warning: These VPN extensions for Chrome leak your DNS

By: Madeleine Dean
2 minute read
chrome vpn extensions leak DNS

Recent reports confirmed that many VPN tools actually leak your IP address to third-party entities. We recently came across a new security report that suggest things are even worse when it comes to Chrome VPN extensions.

As a matter of fact, a whooping 70% of all the tested extensions leak your DNS.

Security researcher John Mason and ethical hacker File Descriptor tested 15 VPN services and found out that 10 of them actually leak your DNS through their browser extensions.

As John Mason explains, Chrome uses DNS Prefetching to reduce website loading latency by predicting what websites you’re going to visit.

Chrome provides users with two modes to set up proxy connections after installing a VPN extension: fixed_servers and pac_script.

The majority of VPN extensions use the pac-script mode. However, this mode allows dynamic HTTPS/SOCKS proxy server host changes. Up to a certain point, this is a good thing as it optimizes the VPN connection depending on what websites users choose to visit.

So, if you use your extension to play games, the script will select a proxy server that’s optimized for playing games.

However, this behavior leaves users vulnerable to DNS leaking. Certain webpage might force visitors to leak DNS requests.

In other words, when you type a website address in the address bar, the suggested URL is actually DNS prefetched. This means that ISPs can then collect this information about the websites that you often visit even if you use a VPN extension.

The list of VPN extensions affected by DNS leaks includes: Hola VPN, TunnelBear, Betternet, Ivacy VPN, DotVPN and more.

The list of extensions that don’t leak your DNS includes: CyberGhost, WindScribe, NordVPN, Private Internet Access and Avira Phantom VPN.

You can mitigate this DNS leak problem by disabling the predictive service from Chrome‘s Settings.

disable predictive service google chrome


In case you want to be secure while surfing the internet, you will need to get a full-dedicated tool to secure your network.  Install now Cyberghost VPN with a 50% discount and secure your computer. It protects your PC from attacks while browsing, masks your IP address and blocks all unwanted access.


DNS leaks may severely affect your online privacy and security. To keep your DNS protected, you can also use these additional security measures:

Next up

2018 List: Best free Android emulators for Windows 10/8.1/7

By: Ivan Jenic
7 minute read

What Android emulator is the best for my Windows PC? Bluestacks MeMu Nox Remix OS Player Droid4X AMIDuOS Windroy Genymotion Xamarin Android Player Andy We’re […]

Continue Reading

New Windows 10 security flaw gives system privileges to hackers

By: Daniel Segun
2 minute read

Recently, a security researcher @SandboxEscaper disclosed in a tweet which has been deleted (the account also has been removed), that the task scheduler is vulnerable […]

Continue Reading

Microsoft devices could support Ultrafast wireless charging in the future

By: Daniel Segun
2 minute read

Microsoft may be developing a new wireless charging system called “Ultrafast’” for its devices, if a newly discovered patent gets approved for mass production. This […]

Continue Reading

Discussions