Facebook cannot seem to get its act together. Fresh off a string of controversies about protecting the information users wish to keep private, the world’s largest social network has admitted that many of its largest games and applications have been leaking user IDs to advertising networks. In fact, the 10 most widely used games and apps on Facebook are transmitting these UIDs, says the Wall Street Journal. Three of the top 10 apps, including Zynga Game Network Inc.’s FarmVille (59 million users) also transmit personal information about a users friends to other companies.
The user ID is the number associated with every user on the site. Before Facebook allowed customized URLs for profile pages, it was easy for anyone to find this number. The user ID is not a private part of a person’s Facebook profile. Knowing someone’s UID will only grant access to the information that user has set to share with “everyone,” which is usually very basic pieces of data like pictures, hometown, age, job, musical preferences, etc. However, when given in bulk, these numbers can provide a database of track-able information to advertisers.
This is not the first UID leak problem the company has faced. In May, the WSJ discovered that Facebook itself was sharing UIDs with advertising networks through its ad sales. Much like today, Facebook admitted the problem and claimed it did not intend to share the user IDs. The company says that the current problem is more challenging.