There are a number of strategies that allow an attacker to break the circle of trust and get into people’s contact lists. A lot of social network users do not realize that their contact lists really is a circle of trust and by adding somebody they do not know—celebrities included—they are opening their data to untrusted parties. Some sites do not have privacy controls in place, or the ones they have do not protect all user data. Even if they do have comprehensive privacy controls, the user is often not obligated to select who can access his/her data and is often.
