A Systematic Literature Review of Inter-Service Security Threats and Mitigation Strategies in Microservice Architectures

Ensuring security is of paramount importance in microservice architectures, given their distributed nature, involving numerous services and network-spanning interactions. This architectural style, which can comprise hundreds to thousands of services, inherently presents a more extensive attack surface compared to traditional monolithic applications. Moreover, the polyglot nature of microservices, which encompasses services developed and deployed using diverse programming languages and technologies, further complicates the security landscape. This paper presents a systematic literature review, analyzing 54 publications specifically in the context of security threats and mitigation strategies within the area of inter-service security in microservice architectures. We observed that the majority of studies focus on presenting methods, models, and guidelines for microservice security, with a significant portion validating these approaches. Publications in the field have increased since 2015, with conference papers being the most common type. Security threats identified are mainly related to security perimeters, attack surfaces, and inadequate monitoring and intrusion detection. There is a notable lack of comprehensive analysis on specific security threats, particularly in inter-service authentication and communication. Mitigation strategies receive more attention than security threats, with extensive discussion on infrastructure defense and secure coding practices. The identified research gap highlights the need for establishing a connection between security threats and their mitigation strategies in microservice architectures. It also underscores the necessity for a standardized taxonomy in microservice security to clarify terminology and consolidate best practices, addressing inconsistencies in the literature and guiding future empirical studies on the practical challenges of implementing security measures.