Nametests.com, the website behind the quizzes, recently fixed a flaw that publicly exposed information of their more than 120 million monthly users — even after they deleted the app. At my request, Facebook donated $8,000 to the Freedom of the Press Foundation as part of their Data Abuse Bounty Program.

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While loading a test, the website would fetch my personal information and display it on the webpage. Here’s where it got my personal information from:

http://nametests.com/appconfig_user

In theory, every website could have requested this data. Note that the data also includes a ‘token’ which gives access to all data the user authorised the application to access, such as photos, posts and friends.

I was shocked to see that this data was publicly available to any third-party that requested it.

In a normal situation, other websites would not be able to access this information. Web browsers have mechanisms in place to prevent that from happening. In this case however, the data was wrapped in something called javascript, which is an exception to this rule.

One of the basic principles of javascript is that it can be shared with other websites. Since NameTests displayed their user’s personal data in javascript file, virtually any website could access it when they would request it.

o verify it would actually be that easy to steal someone’s information, I set up a website that would connect to NameTests and get some information about my visitor. NameTests would also provide a secret key called an access token, which, depending on the permissions granted, could be used to gain access to a visitor’s posts, photos and friends. It would only take one visit to our website to gain access to someone’s personal information for up to two months.

Video proof:

An unauthorised website getting access to my Facebook information

As you can see in the video, NameTests would still reveal your identity even after deleting the app. In order to prevent this from happening, the user would have had to manually delete the cookies on their device, since NameTests.com does not offer a log out functionality.

Source: This popular Facebook app publicly exposed your data for years