Internet of Things (IoT) cybersecurity has become a critical research area due to the massive growth of connected devices and the vulnerabilities they introduce into networks and applications. Research papers in this field address diverse threats such as malware, distributed denial-of-service (DDoS) attacks, man-in-the-middle exploits, data breaches, and unauthorized access to IoT ecosystems. Key studies propose lightweight encryption, intrusion detection systems (IDS), blockchain-based trust management, secure firmware updates, and privacy-preserving protocols tailored for resource-constrained IoT devices. Recent works also explore artificial intelligence and machine learning techniques for anomaly detection, federated learning for distributed security, and zero trust architectures to strengthen device and network resilience. Challenges such as scalability, interoperability, real-time response, and compliance with regulatory frameworks remain active areas of investigation. With the integration of edge/fog computing, 5G/6G, and quantum-resistant cryptography, IoT cybersecurity research continues to focus on building robust, adaptive, and trustworthy IoT infrastructures.