## 1 Introduction
### Scope of the Survey  
In this section, we discuss the current state-of-the-art literature and present a comparative analysis of the existing solutions for security and privacy in smart healthcare systems. Researchers have proposed many surveys on security and privacy prospects for the smart healthcare system, but most of the surveys target electronic healthcare record databases, AI-based healthcare systems, and body area networks, where not all security attacks and their countermeasures are explored. For instance, [PERSON] et al. in [15] presented a layered architecture for a body area network; then, at each layer, its security requirements are investigated. The study investigated various security threats and challenges, particularly for nano-networks and medical devices in body area networks. The authors of [16] explored security and privacy concerns for network-based medical devices. This exhaustive survey includes various medical devices, such as implantable, in and out body sensors, and remote healthcare monitoring interfaces with their regulatory standards and security challenges. The authors describe each security attack vector, such as eavesdropping, information disclosure, DoS, replay, sniffing attacks, etc., and its impact on medical devices. Further, they reveal the shortcomings of the existing regulations and countermeasures applied to address the security issues in network-based medical devices. Then, [PERSON] et al. in [17] studied the security and privacy vulnerabilities of IoT-based healthcare devices. They first proposed an architecture where each level of the architecture is endogenously explored for security and privacy challenges. They discuss attacks, such as authentication, data integrity, access control, key management, and DoS attack with their security solutions. The authors of [18] conducted a comprehensive study of security requirements of Healthcare 4.0, and elaborated on the requirements such as mutual authentication, anonymity, untraceability, perfect forward secrecy, and attack resistance [19]. Further, a taxonomy is presented comprised of various components of Healthcare 4.0, feasible security solutions are proposed. The authors of [20] explored the benefits of blockchain technology in tackling security and privacy attacks in electronic health record systems. They reviewed different blockchain-based schemes used to secure data storage, data sharing, and data audit of healthcare systems. Next, [PERSON] et al. in [21] presented an exhaustive survey of IoT-based healthcare systems, where they focused on IoT-enabled healthcare infrastructure, standard protocols, IoT healthcare security challenges, and market opportunities. In regard to security issues, they reviewed device compromising, information disclosure, and authentication attacks. Furthermore, a threat model is discussed where they emphasise the importance of having a risk management process to counter the security challenges. [PERSON] et al. in [22] reviewed the emerging technologies to offer security solutions in the healthcare environment. They discussed technologies such as IoT, futuristic networks, AI, and big data analytics and the role of these technologies in providing effective healthcare security solutions. However, most of the aforementioned studies explore general security attacks on a specific component of healthcare, such as smart devices, electronic healthcare records, and remote patient monitoring systems; but none of them gives a comprehensive details of those attacks and how they influence healthcare organization and the patient's life. Besides, a few surveys have not explored possible modern-day attacks, and their countermeasures. For instance, the authors of [20] reviewed only blockchain-based security solutions for the healthcare environment. In addition, the study did not investigates the recent attacks lunched on the smart healthcare system and how they impacts on the healthcare organization.