QuizUp, which has been one of the top-selling iOS apps for the past week or so, is full of “shocking” security holes, claims Kyle Richter, the developer behind the popular competing (so..) trivia game Trivium in a blog post.

What I found was at first surprising; then shocking […]

They actually send you other users’ personal information via plain-text(un-hashed); right to your iPhone or iPod touch. This information includes but isn’t limited to: full names, Facebook IDs, email addresses, pictures, genders, birthdays, and even location data for where the user currently is.

I have been able to access the personal information of hundreds of people who I have never met, and had no interaction with other than we both used QuizUp. These people likewise had access to my personal information. It is important to keep in mind these were not people who added me as friends inside of the app, these were complete strangers in every sense … 

As TechCrunch notes, sending unencrypted sensitive data in a way that is vulnerable to interception is exactly what got Path intro trouble, resulting in an $800,000 settlement with the FTC.

Richter declined to go into detail about the exploit he used, but has passed full details to QuizUp developers Plain Vanilla. Plain Vanilla CEO Thor Fridriksson claims there are inaccuracies in the blog claims, though admitted in a statement to TechCrunch that there are weaknesses.

Due to a bug in our third-party network library this encryption could be weakened on some occasions. This issue has been addressed in an update waiting review at Apple. User’s passwords are hashed before we store them in our databases. The user’s Facebook access token is never stored in plain text on the client.

Our user’s address books are not stored on our servers and only used temporarily to help us find your friends. It was a mistake to not hash the contents of the address book before sending to our servers and we are currently changing the client application so it hashes the address book contents before sending to our servers.

The key issues appear to be that although SSL is used to transmit the data, both contact data and Facebook access token were transmitted in plain text and could be easily intercepted.

As of the time of writing, Plain Vanilla says that the server fix has already been made and that a revised version of the app is awaiting approval by Apple.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

One Response to “Top-selling iOS app QuizUp full of “shocking” security holes, some now fixed”

  1. standardpull says:

    Why would you want to give a quiz app any level of access to your Facebook account, your contact list, camera, and GPS?

    The short answer is that it is a bad idea to give a stranger or a corporate entity access to this kind of data.

    If the app is less than good with these features turned off, don’t get fooled: just don’t use the app.

    iOS has privacy controls that work pretty darn well, but if you have become accustom to give apps all the permission they ask for, you are definitely doing it wrong and are looking for trouble.