The privacy of members of online social networks does not only depend on their own privacy settings but also on the privacy settings of their contacts. This phenomenon has given rise to the term interdependent privacy. By now, Facebook established a comprehensive set of privacy settings to restrict the visibility of posts, likes, or the friendlist. Unfortunately, these settings, again, can be made obsolete by other contacts’ settings.
The goal of this thesis is to use the mutual friendship feature of Facebook to develop a tool that automatically uncovers large parts of the friendlist of arbitrary Facebook users. The effectiveness of the tool should be evaluated and the implications in the sense of interdependent privacy for Facebook users should be highlighted.