Bapat, A.D.Pais, A.2020-03-302020-03-302012ACM International Conference Proceeding Series, 2012, Vol., , pp.194-199https://idr.nitk.ac.in/handle/123456789/8949In this paper we address the privacy issues of add-on mechanism supported by browser in private mode. The add-ons enjoy unrestrained access to user sensitive information at all times. This freedom can be misused to create add-ons with malicious intent of violating privacy of the browser. We have designed and implemented an add-on which performs this task in private mode of the browser. This is a clear violation of the goals of private browsing. Mozilla lacks privacy ensuring mechanism against add-ons at browser level. So we have modified the source code of Mozilla Firefox to prevent such behavior of an add-on. It involves runtime monitoring of add-on?s behavior in private mode and notify/block suspicious ones. We have been able to prevent such add-on?s activity using our mechanism. Copyright 2012 ACM.Book chapter