# Security Challenges for Users of Extensible Smart Home Hubs: A Systematic Literature Review
## 3 Results
### Summary of the Literature
The analysis was performed by analyzing roughly 2500 GitHub issues submitted between the release of versions 2020.5 (May 2020) and 2020.12 (December 2020). The impacts of the integration bugs are somewhat similar to the effects of security vulnerabilities, mainly on availability and integrity. The authors summarize their findings into concrete lessons for device integration developers and smart home system designers, highlighting the need for authentication, data validation, and standardization. While the main topic of their paper is feature-oriented, the authors argue that the outcomes are somewhat related to cybersecurity. Also in 2022, [PERSON] et al. (2022) surveyed different styles of smart home systems, including IFTTT, Google Home, Apple HomeKit, Samsung SmartThings, Home Assistant, and openHAB. The survey explains the general architecture of smart home systems and gives examples of security architectures. Further, it covers common attack categories divided into perception layer, communication layer, and application layer attacks. Among the application layer attacks are third-party app backdoors, over-privileged third-party apps, vulnerable automation rules, and fragile cross-platform interactions. Finally, it introduces the security requirements of smart home systems and indicates open research questions for attacks and defenses. These questions include exploiting devices, permissions, authentication, and automation, mitigating data security risks of third-party apps, and ensuring the security of cross-platform data sharing. In another survey from 2022, [PERSON] and [PERSON] [30] presented the general security of smart home systems seen through the lens of the Internet of Things. The authors introduce a broad new definition of smart home systems and provide background on general challenges in the industry: scale, diversity, fragmentation, resource restrictions, cyber-physical coupling, and complex temporality. Typical attack technologies and models are introduced, as well as typical defense approaches and common architecture types of smart home systems. The authors also stress the importance of soft security (human factors that impact security) in achieving overall security of smart home systems. The focus of this survey is broader than several of the others combined, and it, therefore, also focuses on the general application of software-defined networks, blockchain, and other technologies in smart home systems. Because of this focus, future work suggested includes creating a general secure architecture, finding security solutions that work on low-performance devices, and exploring techniques for overcoming smart home fragmentation issues. The following year, 2023, [PERSON] and [PERSON] [4] proposed adjusting and implementing the IETF Manufacturer Usage Description standard on extendable smart home gateways to accelerate the technology adoption and improve the security of smart home gateways. This work uses the threat model published in 2022 by the same authors [1]. IETF MUD is a standardized description provided by manufacturers to indicate the expected uses of the device, allowing other requests to be blocked on the network level. The architecture proposed by the authors uses access requirement information from Home Assistant add-ons to construct a gateway-level MUD file to enforce network traffic rules utilizing a firewall. This work is one of several that use extensible smart home gateways to retrofit smart home devices with new security features. Also in 2023, [PERSON] et al. [31] reviewed the harms of the smart home from an interdisciplinary perspective, among which the perspectives of information security, human-computer interaction, social sciences, and law were included. From the information security perspective, the authors write that harms, vulnerabilities, and risks are formalized by standards like CVE, CWE, OWASP IoT TOP 10, STRIDE, and CAPEC. Furthermore, the security analysis of smart homes is divided into three levels: smart home devices, smart home networks, and security protocols.