There are many benefits of combining IoT devices with cloud computing, which can help exploit each service's potential better and increase computing and storage capacity. However, there are also several threats in this area that pose serious security challenges. In this paper, the author has searched for the vulnerabilities and threats specific to the Cloud of Things through keyword analysis, and then completed a deeper analysis of the relevant literature, has identified the security solutions that can contribute to maintaining adequate security of data and services. The focus was on the scientific publications in Elsevier's Scopus database, in which the author sought answers to the following questions: "What are the most common vulnerabilities that threaten the interconnection of IoT solutions and cloud computing?" and "What are the most effective security solutions that can be applied to protect data, devices, and systems in a Cloud of Things solution?". The research results have shown that there are strong links between the threats, which can only be mitigated by a complex and comprehensive security architecture.