The Internet of Things (IoT) has seen significant advancements, leading to a paradigm shift in the digital landscape. However, these advancements have introduced new cybersecurity challenges, particularly in protecting IoT devices and services. Cloud-based IoT systems, enabled by Platform-as-a-Service (PaaS) and Infrastructure-as-a-Service (IaaS) models, offer flexibility and scalability but also pose additional security risks. The integration of IoT with cloud systems involves continuous communication, making them susceptible to adversarial attacks, eavesdropping, MITM attacks, and packet tampering. These security concerns are critical, especially for IoT devices in essential systems like power grids, where a cyber-attack could cause widespread outages. This paper explores the security challenges associated with cloud-based IoT systems, focusing on the unique risks posed by the convergence of traditional and cloud-based systems. It highlights the pressing security concerns associated with the widespread adoption of IoT devices and services, proposing viable solutions to bridge existing security gaps while anticipating future challenges. The paper categorizes IoT devices into ten distinct groups based on their specific purpose and application, identifying their specific security and privacy issues. It also suggests proactive strategies to mitigate these risks, thereby strengthening the overall security of IoT devices and services. The paper addresses three research questions: (1) Can we comprehensively categorize the various cloud-based IoT devices based on their specific purpose and address their existing or future security/privacy issues? (2) What mitigation approaches can be employed in each category to address the identified security/privacy issues? (3) How viable is the implementation of standardized uniform solutions across all reported categories? The paper discusses the security challenges associated with each category, including consumer-oriented IoT, children's IoT, healthcare IoT, and industrial IoT. It highlights the vulnerabilities in these systems, such as insecure communication channels, weak authentication, and inadequate data protection. The paper also proposes mitigation approaches, including secure authentication mechanisms, encryption techniques, and blockchain-based solutions, to address these security issues. The paper concludes that addressing the security challenges in cloud-based IoT systems requires a comprehensive approach, including the development of robust security frameworks, the implementation of standardized solutions, and the collaboration between manufacturers, cloud providers, and policymakers to ensure the safety and privacy of IoT devices and services.The Internet of Things (IoT) has seen significant advancements, leading to a paradigm shift in the digital landscape. However, these advancements have introduced new cybersecurity challenges, particularly in protecting IoT devices and services. Cloud-based IoT systems, enabled by Platform-as-a-Service (PaaS) and Infrastructure-as-a-Service (IaaS) models, offer flexibility and scalability but also pose additional security risks. The integration of IoT with cloud systems involves continuous communication, making them susceptible to adversarial attacks, eavesdropping, MITM attacks, and packet tampering. These security concerns are critical, especially for IoT devices in essential systems like power grids, where a cyber-attack could cause widespread outages. This paper explores the security challenges associated with cloud-based IoT systems, focusing on the unique risks posed by the convergence of traditional and cloud-based systems. It highlights the pressing security concerns associated with the widespread adoption of IoT devices and services, proposing viable solutions to bridge existing security gaps while anticipating future challenges. The paper categorizes IoT devices into ten distinct groups based on their specific purpose and application, identifying their specific security and privacy issues. It also suggests proactive strategies to mitigate these risks, thereby strengthening the overall security of IoT devices and services. The paper addresses three research questions: (1) Can we comprehensively categorize the various cloud-based IoT devices based on their specific purpose and address their existing or future security/privacy issues? (2) What mitigation approaches can be employed in each category to address the identified security/privacy issues? (3) How viable is the implementation of standardized uniform solutions across all reported categories? The paper discusses the security challenges associated with each category, including consumer-oriented IoT, children's IoT, healthcare IoT, and industrial IoT. It highlights the vulnerabilities in these systems, such as insecure communication channels, weak authentication, and inadequate data protection. The paper also proposes mitigation approaches, including secure authentication mechanisms, encryption techniques, and blockchain-based solutions, to address these security issues. The paper concludes that addressing the security challenges in cloud-based IoT systems requires a comprehensive approach, including the development of robust security frameworks, the implementation of standardized solutions, and the collaboration between manufacturers, cloud providers, and policymakers to ensure the safety and privacy of IoT devices and services.