Certain Chrome Extensions Found Leaking DNS Queries

[Wilhelm]

Security researcher John Mason discovered that the configurations in some VPN extensions fail to mask DNS prefetching in the Chrome browser.

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 Is Your VPN Leaking?
Be careful around certain VPN providers. Not all are created equal and some can fail to fully mask your internet searches.

SecurityWatchCase in point: New research has uncovered that several VPN services that work over a Chrome browser extension actually appear to be leaking DNS queries, exposing the user's internet activity to an ISP.

John Mason, a security researcher at TheBestVPN.com, detailed the problem in a write-up that studied 17 different VPNs that function via Chrome browser extensions. He and another ethical hacker originally found that at least 10 of the browser extensions (many of which were free) leaked the DNS queries.

DNS queries essentially involve your computer communicating requests for whatever internet websites you wish to visit. Normally, a VPN service would mask these queries.

But Mason found that the browser extensions were leaking the data due to a Chrome function called "DNS prefetching," which is designed to help it load websites faster. To do so, Chrome will prefetch domain names that appear in the hyperlinks that pop up in your browser. The best example is when Chrome encounters a Google search result page; the browser will extract the domain name from each hyperlink and resolve each one to an IP address.

However, Mason discovered that the configurations in some VPN Chrome extensions fail to mask the DNS prefetching, and can instead expose the DNS queries to an internet service provider. Since Mason's write-up went public, a few of the VPN services have patched the problem, but not all. The biggest provider, Hola VPN, told PCMag that it doesn't intend on changing its practices.

"Hola is an unblocker — its main goal is to allow people all over the world to watch content without any form of censorship or content manipulation," the VPN provider said in an email. "For users seeking not to 'unblock,' but to keep their identity completely hidden, Hola is not the right unblocker to use."

Another VPN provider, Betternet, claimed it had fixed the problem, but Mason said his testing showed that the DNS leaking persists.

Mason offers a list of VPN Chrome extensions that are affected; those that weren't included NordVPN$3.29 at NordVPN - 2 year plan, a PCMag Editors' Choice. For people concerned about the leaking, one easy solution is to avoid accessing your VPN over a browser extension. Many, if not all VPN services, let you access them over a Windows or Mac-based client.