Facebook privacy revisited: Privacy Mirror version 2

Facebook’s recent changes to its privacy system has been garnering a lot of attention and not a lot of it is good. Both the EFF and Kaliya Hamlin (via ReadWriteWeb) have written up their takes on the matter and, all in all, I think they are decent assessments.

With all the supposed changes in Facebook’s privacy system, I decided to revisit my work with Privacy Mirror (you can catch the backstory: here and then here). Having retested PM with both friends and strangers, here’s what I’ve learned: Plus ça change, plus c’est la même chose.

The more things change, the more they stay the same.

Facebook’s inconsistent treatment of privacy still remains. In a nutshell, what a 3rd party developer can see in your profile, having been granted access to you via your friends, directly depends on whether you have the same application they do. If you and your friends use the same Facebook app, then the 3rd party developer will see your profile (and photos and posts, etc.) as if that developer was your friend. If you do not use the same Facebook app that your friend does, then the 3rd party application is subject to a different set of constraints.

I question whether the recent changes Facebook has instituted have even remotely satisfied Commissioner Stoddart’s concerns with Facebook, specifically 3rd party access to user information. Although users can control the scope of disclosure of their posts a bit better, defaulting settings to “Everyone” access as well as potentially making user’s social graphs public undermines any attempt to cast Facebook in a pro-user control light.

Looking beyond the Privacy Mirror

Over the last two weeks, I have been using my homegrown Facebook application, Privacy Mirror, as a means of experimenting with Facebook’s privacy settings. Although Facebook provides a nice interface to view your profile through your friends’ eyes, it does not do the same for applications. I built Privacy Mirror with the hopes of learning what 3rd party application developers can see of my profile by way of my friends’ use of applications. I have yet to speak with representatives of Facebook to confirm my findings, but I am confident in the following findings.

Imagine that Alice and Bob are friends in Facebook. Alice decides to add a new application, called App X, to her profile in Facebook. (For clarity’s sake, by “add”, I mean that she authorizes the application to see her profile. Examples of Facebook applications include Polls, Friend Wheel, Movies, etc.) At this point, App X can see information in Alice’s profile. App X can also see that Alice is friends with Bob; in fact, App X can see information in Bob’s profile. Bob can limit how much information about him is available to applications that his friends add to their profiles through the Application Privacy settings. In this case, let’s imaging that Bob has only allowed 3rd party applications to see his profile picture and profile status.

Further findings from the Privacy Mirror experiment

I find that I rely on my debugging skills in almost every aspect of my life: cooking, writing, martial arts, photography… And it helps when you’ve got friends who a good debuggers as well. In this case, my friends lent a hand helping me figure out what I was seeing in my Privacy Mirror.

The following is a snapshot of the Application Privacy settings I have set in Facebook:

Facebook Application Privacy Settings

Given these settings, I would expect that the Facebook APIs would report the following to a 3rd party application developer:

  • My name
  • My networks
  • My friends ids
  • My profile status