Today, a number of people user use online social network service. While other web sites of traditional forms treat only photos and articles of users, SNS covers more sort of information. SNS privacy issue receives more attention because SNS users upload and update information about them in real time. Existing researches mainly concentrate about extracting profiles from each user or connections between users. In this paper, we propose a possible privacy attacking method that an adversary may use, and show that the method can be adopted in real social network service form as the third party application. Especially, we show how the application works to analyze threats to which SNS users can be exposed, and to show in what way users should react when using SNS.