Tech Post: Browser Fingerprints

In our second Reality Dispatch Tech Brief, we cover Browser Fingerprints.  Yesterday we covered using VPNs to work around restrictions on what sites you can browse and anyone seeing you browse them.  Today we cover “super cookies”, or browser fingerprints, that identify you even when you’re trying to fly under the radar – and how to beat them.

What is a Browser Fingerprint?

Your computer is identifiable.  Not just by I.P. Address, which our VPN article can help you circumvent, but by other unique characteristics, which can be read using JavaScript:

  • Screen resolution
  • Choice of browser (Firefox, Chrome, Safari…)
  • What plug-ins for your browser are installed?  Including what media extensions.
  • Time Zone setting
  • Operating System (Platform)
  • Installed (Available) Fonts
  • Cookie support, Touchscreen support
  • HTML5 Canvas support

That last one is huge.  It’s an HTML5 extension for drawing, that exposes some very consistent timing and resolution data.

You can test your trackability here or here.  Run it several times; you’re likely to see the same fingerprint.

What does this mean?

Your Browser Fingerprint is essentially a server-side super-cookie.  Nefarious companies (that’s all of them) can identify you, sell your browsing interaction with them to aggregation advertising systems,  which monetize your browsing.  But the bigger concern is that they know who you are and everything you do online.

Fighting Browser Fingerprinting

Unfortunately, you don’t have many options here.  Browsers expose too much, because JavaScript must provide a lot of operational environment data to work effectively.  If you block JavaScript, you will effectively prevent browser fingerprinting… but most sites will break also.

One thing you can do is dedicate a distinct browser, with a VPN, and install a fingerprint blocker such as:

These don’t precisely block fingerprinting.  What they do is introduce “noise” – random timing entropy – into the HTML5 Canvas mentioned above.  And they change that noise regularly.

So, if you install one of these and visit the BrowserLeaks Canvas page, you will see a specific number for “Signature.”  And then, if  you click “Generate New Noise” in CanvasDefender and reload that page, or simply reload the page in CanvasBlocker / FireFox, you get a new signature.  This hides your identity.

As a practical matter,  you should use one of these for your main browsing and the other for your privacy browsing.  Realistically, you probably aren’t using Brave, Opera, Internet Explorer, Edge, Safari or Firefox for your primary browser.

  • Brave is privacy oriented, but not flexible enough yet without custom search.
  • Opera was the first great indie-browser, but is now Chinese-owned and Blink-based, reducing the value-add vs risk proposition.
  • If you’re still using Internet Explorer… change.
  • Microsoft Edge is, in the R/D view, an under-rated fast, compatible browser.  The trouble is… the web is filled with unwanted ads and videos.  Edge is great but doesn’t have the extension support of Chrome or Firefox.

2/3 of the world uses Chrome.  So keep using Chrome when you just don’t care about hiding your identity.  Your bank, Best Buy, Netflix, Amazon… they already know all about you.  Including from your login.  So disguising yourself won’t make any difference and could get you locked out of your account.

What Else Should You Do?

The other important thing is, disable third party cookies and clear cookies on exit.  This can be pretty inconvenient…

  • You will have to log into sites frequently
    • Although if you save your login credentials, that’s less bad
  • Blocking third party cookies will break a lot of discussion forums on websites
    • You can enable those as “Allow” white lists, but it’s inconvenient
  • Some sites simply won’t work in that state.

So, again, you may find it best to do this in the privacy browser with the VPN and Browser Fingerprint-preventing extensions, allowing your “daily driver” browser to expose you where you’re already exposing yourself anyhow.

Summary

The combination of a VPN, privacy mode and selective cookie blocking can make you much harder to identify online, dramatically improving your privacy.  Each of these can be slightly inconvenient, but the pay off – preventing the corporations and government from knowing everything you look up and do online – may be worth it.

 

3 thoughts on “Tech Post: Browser Fingerprints

    • Oops! Using the links given in the article, I find that I am NOT safe from canvas fingerprinting. I will have to try again with a newer OS.

      • It is eye-opening, isn’t it!

        The OS won’t make the difference; you need an extension that introduces noise into the canvas.

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