Web 2.0 Security and Privacy 2008 (in conjunction with 2008 IEEE Symposium on Security and Privacy). Oakland, CA. 22 May 2008.
Social networking platforms integrate third-party content into social networking sites and give third-party developers access to user data. These open interfaces enable popular site enhancements but pose serious privacy risks by exposing user data to third-party developers. We address the privacy risks associated with social networking APIs by presenting a privacy-by-proxy design for a privacy-preserving API. Our design is motivated by an analysis of the data needs and uses of Facebook applications. We studied 150 popular Facebook applications and found that nearly all applications could maintain their functionality using a limited interface that only provides access to an anonymized social graph and placeholders for user data. Since the platform host can control the third party applications' output, privacy-by-proxy can be accomplished by using new tags and data transformations without major changes to either the platform architecture or applications.