The Nearly Unblockable Tracking Tool That You Need To Be Aware Of

There’s a scummy new tracking tool in cyber-town. It’s called “canvas fingerprinting” and it’s being used by such websites as WhiteHouse.gov.

Like other tracking tools, canvas fingerprints are used to build profiles of users based on the websites they visit — profiles that shape which ads, news articles, or other types of content are displayed to them.

But fingerprints are unusually hard to block: They can’t be prevented by using standard Web browser privacy settings or using anti-tracking tools such as AdBlock Plus.

The technology instructs your web browser to create a hidden image. Keyword: hidden. Because it’s something they don’t want you to know about, right? That hidden image can then be used to track your browsing.

Why the new technology? Because people don’t like to be tracked and too many people have learned how to prevent tracking by cookies. This technology doesn’t use cookies and there’s no easy way to block it.

The good news is that you can prevent it from happening by disabling JavaScript. The bad news is that almost every website uses JavaScript, and if you disable it, browsing the web is going to suck. The best option, at this point, seems to be a browser plugin called NoScript, which allows you to turn off JavaScript by default for untrusted websites and enable it on a site-by-site basis for trusted ones. I’ve been using NoScript for Firefox for several years and it’s pretty painless.

Read more about canvas fingerprinting at ProPublica, or if you’re nerd elite, check out the super geeky pdf of the scientific report.