Facebook, the social networking platform that has redefined communications, has millions of users. And according to University of Virginia computer science major Adrienne Felt, all of these users should be concerned about security.
Felt, a fourth-year student in the School of Engineering and Applied Science at U.Va., leads a research project on privacy issues surrounding social networking platforms and is investigating the information sharing that occurs when users download a Facebook application -- a program that allows the user to interact with other users in interesting ways, from sharing music to playing games.
Although these applications add variety to a Facebook user's profile page, they also increase the user's vulnerability. Here's how: anyone with an account on Facebook can create an application. Although this application appears as if it is part of Facebook's platform, it is actually running on application developer's server. When a user installs an application, that application's developer is given the ability to see everything the user can see -- name, address, friends' profiles, photos, etc.
"The Facebook privacy policy always seemed unsatisfactory to me," said Felt, an experienced Facebook application developer.
It was this unsettling feeling that led her to investigate Facebook's vulnerabilities as a student researcher working with David Evans, an associate professor in U.Va.'s Department of Computer Science. With the help of fourth-year physics major Andrew Spisak, Felt examined the 150 most popular Facebook applications. She discovered that 8.7 percent of these applications needed no personal information to run, while 82 percent needed only the user's public information (name, network, list of friends). Still, 9.3 percent require a user's private information in order to function.
"Since all applications receive access to private information," said Felt, "this means that 90.7 percent of Facebook's most popular applications unnecessarily have access to private data."
There are currently no restrictions on what applications (and their developers) can do with user data, and though the Facebook "Terms of Use" warn developers not to abuse the data they have access to, Facebook cannot enforce this rule, Felt says. In fact, when a user installs an application, the user's computer communicates with the Facebook servers and the Facebook servers then communicate with the application developer's servers. Once users' private data leave the Facebook servers, the company has no way of knowing what happens to it.
"An application developer could easily acquire personal information for millions of users," said Evans. "There is a risk it could be used to launch targeted phishing attacks, exploited by identity thieves or sold to marketing companies."
Felt's goal is to make users more aware of how their private information is being used -- and to close this privacy loophole.
She has developed a privacy-by-proxy system -- a way for Facebook to hide the user's private information, while still maintaining the applications' functionalities. Under Felt's system, at the point at which the Facebook server is communicating with the application developer's server, the Facebook server would provide the outside server with a random sequence of letters instead of the user's name (and other personal information).
Felt is working on refining the privacy-by-proxy design and building a prototype implementation. "This is the first step," she said. "Hopefully, the research findings and proposed solution will trigger more responsible privacy and information management policies from social networking sites and will better inform users."
