Online Social Networks (OSNs) are currently playing a crucial role in our everyday social life. Their great growth has sparked the interest of hackers and individual users that try to disclose as much information as possible, which in many cases unfortunately is possible. In such events, the users’ privacy settings are bypassed by the leakage of their shared media content. To address this challenging but important research problem, we introduce a new distributed scheme for media content sharing on online social networks that may minimize users’ privacy exposure, through automated procedures. The novelty of the proposed scheme is the ability to enforce a user’s privacy policies across multiple online social networks, even if she is not subscribed to all of them, without using a trusted third party. Moreover, the proposed framework is a step towards enabling OSNs to interact, exchange information with equal rights, independently of their size, focus and underlying infrastructure.