What are DNS, WEBRTC, and IPV6 Leaks & How to Prevent ThemLast Updated by Joel Timothy on March 05, 2019
Internet privacy is a huge concern for many people, and whenever you’re online, your information is at risk of being exposed.
Third-parties like marketing networks can track your browsing history and habits, ISPs can see every query and data you send, and cybercrime is always evolving.
With a VPN, you can hide your IP and protect your privacy when online, however, not all VPNs are created equal.
What is a VPN leak?
Usually, when you send encrypted data through a VPN, nobody should be able to see your public IP address, and your DNS requests shouldn’t be visible to any DNS server other than that of the VPN.
A leak is a security flaw that causes a VPN to reveal information to your ISP and other third parties.
Common VPN leaks
1 DNS leaks
A DNS translates domain names into machine read IP addresses to facilitate browsing. When you type the name of a website, a query is sent to the ISP’s DNS server which response is the IP address, and, therefore, ISPs can monitor and log all requests you submit.
You can test for a DNS leak using websites like DNSLeak.com and dnsleaktest.com. The tests will give you the name of the DNS server you are using, and if it indicates your ISP’s server, you have a leak.
How to Prevent DNS Leaks
2 WebRTC Leaks
Web Real-Time Communication allows web browsers to communicate P2P without the need for an extra add-on. While the technology results in faster speeds and less lag, it also poses a huge privacy and security risk when using a VPN.
For two devices to communicate via WebRTC, they need each other’s IP address. A direct connection like this can bypass VPN encryption leaving third-party website able to identify your real IP address by exploiting browsers like Firefox, Opera, Chrome, and Brave.
Typically, this is achieved through STUN requests to the browser, and the result is a WebRTC leak.
Daniel Roesler exposed this vulnerability on his GitHub page in 2015.
How to prevent WebRTC Leaks
3 IPv6 Leaks
IPv6 addresses are the next generation of the protocol and the solution to the exhaustion of the current format. Although IPv6 was devised to improve online communications, it also poses some serious privacy and security issues, mostly because adoption has been slow.
If a third-party makes an IPv6 request, your identity could be exposed; however, some VPNs block IPv6 traffic altogether to avoid this problem.
Check if your VPN prevents IPv6 leaks at www.ipleak.net
How to Prevent IPv6 Leaks
Solving DNS, WebRTC, and IPv6 Leaks at one go
Though there are various ways to resolve leaks, some of them are complicated, and others just not effective.