The Fifth Generation of Communication Networks (5G) envisions a broader range of servicescompared to previous generations, supporting an increased number of use cases and applications. Thebroader application domain leads to increase in consumer use and, in turn, increased hacker activity. Dueto this chain of events, strong and efficient security measures are required to create a secure and trustedenvironment for users. In this paper, we provide an objective overview of5G security issues and theexisting and newly proposed technologies designed to secure the5G environment. We categorize securitytechnologies usingOpen Systems Interconnection (OSI)layers and, for each layer, we discuss vulnerabilities,threats, security solutions, challenges, gaps and open research issues. While we discuss all sevenOSIlayers, the most interesting findings are in layer one, the physical layer. In fact, compared to other layers,the physical layer between the base stations and users’ device presents increased opportunities for attackssuch as eavesdropping and data fabrication. However, no singleOSI layer can stand on its own to provideproper security. All layers in the5G must work together, providing their own unique technology in an effortto ensure security and integrity for5G data
