This paper gives insights into the most important existing problems of security and privacy of the Cloud Computing (CC), Internet of Things (IoT) and Cloud of Things (CoT) concepts especially confidentiality issue. With the evolution of ubiquitous computing, everything is connected everywhere, therefore these concepts have been widely studied in the literature. However, intrusions and vulnerabilities will be more recurrent due to the systems complexity and the difficulty to control each access attempt. To tackle this issue, researchers have been focused on various approaches enforcing security and privacy. In the present paper, risk factors and solutions regarding these technologies are reviewed then current and future trends are discussed.
