WASHINGTON: Popular social networking websites' users could be leaking their personal information to tracking sites, warn researchers at Worcester Polytechnic Institute (WPI).
They have found that the practices of many popular social networking sites typically make that personal information available to companies that track Web users' browsing habits, and allow them to link anonymous browsing habits to specific people.
"When you sign up with a social networking site, you are assigned a unique identifier," said Craig Wills, professor of computer science at WPI, who conducted the study with an industry colleague.
He said, “This is a string of numbers or characters that point to your profile. We found that when social networking sites pass information to tracking sites about your activities, they often include this unique identifier.”
“So now a tracking site not only has a profile of your Web browsing activities, it can link that profile to the personal information you post on the social networking site. Now your browsing profile is not just of somebody, it is of you," he added.
Like most commercial websites, online social networks use third-party tracking sites, called aggregators, to learn about the browsing habits of their visitors.
Cookies are maintained by a Web browser, and contain information that enables tracking sites to build profiles of the websites visited by a user.
Each time the user visits a new website, the tracking site can review those cookies and serve up ads that might appeal to the user. With a unique identifier, a tracking site could gain access to a user's name, physical address, email address, gender, birth date, educational and employment information and much more.
With the "leakage" of personal information, there is a significant risk of having one's identity linked to an inaccurate or misleading browsing profile.
When a computer is used by more than one person, or a person browses for curiosity rather than intent, it leaves room for misinterpretation, he notes.
"Tracking sites don't have the ability to know if, for example, a site about cancer was visited out of curiosity, or because the user actually has cancer. Profiling is worrisome on its own, but inaccurate profiling could potentially lead to issues with employment, health care coverage, or other areas of our personal lives," Wills added.
The study was presented in Barcelona at the Workshop on Online Social Networks.