Technology specific expert knowledge is often required to analyse security configurations and determine potential vulnerabilities, but it becomes difficult when it is a new technology such as Fog computing. Furthermore, additional knowledge is also required regarding how the security configuration has been constructed in respect to an organisation's security policies. Traditionally, organisations will often manage their access control permissions relative to their employees needs, posing challenges to administrators. This problem is even exacerbated in Fog computing systems where security configurations are implemented on a large amount of devices at the edges of Internet, and the administrators are required to retain adequate knowledge on how to perform complex administrative tasks. In this paper, a novel approach of translating object-based security configurations in to a graph model is presented. A technique is then developed to autonomously identify vulnerabilities and perform security auditing of large systems without the need for expert knowledge. Throughout the paper, access control configuration data is used as a case study, and empirical analysis is performed on synthetically generated access control permissions.