Privacy Badger (alpha) – a new browser extension by the EFF

Douglas Crawford

Douglas Crawford

May 6, 2014

The Electronic Frontier Foundation has built up an extremely respected and well-earned reputation for itself as a champion of online privacy and digital rights, so when it releases a new browser extension (currently available for Firefox and all versions of Chrome) which ‘blocks spying ads and invisible trackers,’ it’s worth paying attention.

The EFF sets out its mission statement as follows,

Privacy Badger was born out of our desire to be able to recommend a single extension that would automatically analyze and block any tracker or ad that violated the principle of user consent; which could function well without any settings.

Completely open source and based on a modified version of the AdBlock Plus engine, Privacy Badger differs from extensions such as Adblock Plus, Ghostery and Disconnect mainly in that it does not use a blacklist to determine which elements are blocked, but monitors when websites send information they have been instructed not to by a ‘Do not track’ request, and blocks them accordingly,

This extension is designed to automatically protect your privacy from third party trackers that load invisibly when you browse the web. We send the Do Not Track header with each request, and our extension evaluates the likelihood that you are still being tracked. If the algorithm deems the likelihood is too high, we automatically block your request from being sent to the domain. Please understand that Privacy Badger is in beta, and the algorithm’s determination is not conclusive that the domain is tracking you.

privacy badger 1

It takes time for Privacy Badger to identify tracker sites

privacy badger 2

After a while though, it learns which domains are trackers

In other words, it acts in much the same way as the RequestPolicy Firefox extension, and in use is simplicity itself,

Our extension has three states. Red means block the tracker. Yellow means that we don’t send cookies or referers to the tracker. Green means unblocked (probably because the third party does not appear to be tracking you). You can click on the Privacy Badger icon in your browser’s toolbar if you wish to override the automatic blocking settings. Or, you can browse in peace as Privacy Badger starts finding and eating up web trackers one by one.’

When you first use Privacy Badger all domains will show green, but as the extension analyses their behavior and ‘learns’ which domains track you they will be identified and automatically blocked.

One area of concern for us at present is that a rather large whitelist exists, aimed at preventing popular sites from being ‘broken’ by the extension. While this is an understandable concession to practicality, we are glad to note that ‘in the long term we hope to phase out the whitelist as these third parties begin to explicitly commit to respecting Do Not Track.’

One promised future development that we are particularly excited about is ‘we will be adding fingerprinting countermeasures in a future update!’ Evading this nefarious form of online tracking is at present almost impossible (and any measures taken to evade other forms of tracking actually increase the uniqueness of your browsers’ fingerprint), so this is great news. We discuss browser fingerprinting in some depth here.

Our take

It’s always great to see new privacy enhancement tools, and with EFF backing Privacy Badger may have the weight behind it to encourage more websites to abide by Do Not Track instructions (as doing so will get them unblocked by Privacy Badger). In addition to this, the fact that Privacy Badger is an easy to use one-stop-shop for browser privacy makes it ideal for use by ordinary web users.

For now however, tech savvy netizens who already have Adblock Plus, Disconnect, Ghostery etc. (see our list of recommended extensions for Firefox and Chrome) installed on their browsers will probably not see any benefit from using Privacy Badger (in fact Privacy Badger is probably less effective at preventing tracking).

It is still early however, and Privacy Badger is still in alpha. Not only are there likely a great many bugs that need ironing out, but additional refinements and functionality will be added (and we are particle excited by the promised anti-fingerprinting measures!).

Privacy Badger is available from here.

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