Thousands more secret trackers could be following you online

Privacy
(Image credit: Shutterstock / Valery Brozhinsky)

With Google all set to wage a war against online trackers, AdGuard, which develops a line of ad blocking and privacy protection browser extensions, has released a list of over six thousand CNAME-based web trackers.

CNAME (Canonical name) is a DNS record used to alias one domain name to another - so thanks to CNAME it’s possible to run multiple services from a single IP address. However, online advertisers and other unscrupulous agents abuse CNAME records to hide tracking scripts behind trusted domains.

“As content blocking has become widespread, most tools for excessive tracking proved to be fairly useless. But with the market moving more and more towards massive data collection, the tendency was to push it as far as possible. Some opt for a blatant approach, and some seek more inventive ways to collect users' data," noted AdGuard CEO Andrey Meshkov in a blog post as he shared the list of CNAME abusing trackers.

Arm yourself

Reportedly, one of the main reasons for the growing use of CNAME-based trackers is that there isn’t a law against using CNAME records deceptively.

However, user’s aren’t completely defenseless. Last year, the privacy-focussed Brave browser announced its ability to detect and block tracking cookies from cloaked CNAMEs. And Firefox users can protect themselves using third-party extensions such as uBlock Origin and AdGuard.

However, according to Meshkov Safari, Chromium, and Chromium-powered browsers like Google Chrome and Microsoft Edge, can’t yet examine DNS. This means they can only be effective against CNAME-based trackers using filter lists such as the one released by AdGuard.

“Thanks to our own DNS server, plus a set of standalone and browser-based content blocking tools, we've been able to hunt the hunters (or rather track the trackers), list them, and block them,” notes Meshkov adding that the company has shared the list on GitHub for other content blockers to use as well.

Via The Register

Mayank Sharma

With almost two decades of writing and reporting on Linux, Mayank Sharma would like everyone to think he’s TechRadar Pro’s expert on the topic. Of course, he’s just as interested in other computing topics, particularly cybersecurity, cloud, containers, and coding.

Read more
Fingerprint
Profit over privacy? Google gives advertisers more personal info in major ‘fingerprinting’ U-turn
female graphic designer pointing with finger on laptop computer during collaboration with male colleague on common project in coffee shop
How sites are falsely blaming ad blockers for site breakdowns
Ad Blocker on Laptop
Best ad blockers of 2025
A finger touching the google chrome icon in the Windows 10 start menu
A new Chrome browser highjacking attack could affect billions of users - here's how to fight it
Abstract illustration of a young woman looking at a smartphone, as large eyes peek through from her hair
Want to hit restart on your online presence? Here's 5 tools you need to stay truly private online
Homepage of CloudFlare website on the display of PC, url - CloudFlare.com.
"Network blocking is never going to be the solution" – Cloudflare slams anti-piracy tactics
Latest in Software & Services
TinEye website
I like this reverse image search service the most
A person in a wheelchair working at a computer.
Here’s a free way to find long lost relatives and friends
A white woman with long brown hair in a ponytail looks down at her computer in a distressed manner. She is holding her forehead with one hand and a credit card with the other
This people search finder covers all the bases, but it's not perfect
That's Them home page
Is That's Them worth it? My honest review
woman listening to computer
AWS vs Azure: choosing the right platform to maximize your company's investment
A person at a desktop computer working on spreadsheet tables.
Trello vs Jira: which project management solution is best for you?
Latest in News
Ray-Ban Meta Smart Glasses
Samsung's rumored smart specs may be launching before the end of 2025
Apple iPhone 16 Review
The latest iPhone 18 leak hints at a major chipset upgrade for all four models
Quordle on a smartphone held in a hand
Quordle hints and answers for Monday, March 24 (game #1155)
NYT Strands homescreen on a mobile phone screen, on a light blue background
NYT Strands hints and answers for Monday, March 24 (game #386)
NYT Connections homescreen on a phone, on a purple background
NYT Connections hints and answers for Monday, March 24 (game #652)
Quordle on a smartphone held in a hand
Quordle hints and answers for Sunday, March 23 (game #1154)