Identifying high-risk over-entitlement in access control policies using fuzzy logic

作     者：Simon Parkinson Saad Khana Simon Parkinson;Saad Khana

作者机构：Department of Computer ScienceUniversity of HuddersfieldHuddersfieldHD13DHUK 

出 版 物：《Cybersecurity》 (网络空间安全科学与技术（英文）)

年 卷 期：2022年第5卷第2期

页      面：75-91页

核心收录：

学科分类：0810[工学-信息与通信工程] 1205[管理学-图书情报与档案管理] 0839[工学-网络空间安全] 08[工学] 0835[工学-软件工程] 0811[工学-控制科学与工程] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：This work was undertaken during a project funded by the UK’s Digital Catapult Researcher in Residency Fellowship programme (Grant Ref: EP/M029263/1) The funding supported the research, development, and empirical testing presented in this paper 

主　　题：Fuzzy control Fuzzy systems Security Access control policies Security analysis Risk Fuzzy logic Risk-adaptive access control 

摘      要：Analysing access control policies is an essential process for ensuring over-prescribed permissions are identified and removed. This is a time-consuming and knowledge-intensive process, largely because there is a wealth of policy information that needs to be manually examined. Furthermore, there is no standard definition of what constitutes an over-entitled permission within an organisation’s access control policy, making it not possible to develop automated rule-based approaches. It is often the case that over-entitled permissions are subjective to an organisation’s role-based structure, where access is be divided and managed based on different employee needs. In this context, an irregular permission could be one where an employee has frequently changed roles, thus accumulating a wide-ranging set of permissions. There is no one size fits all approach to identifying permissions where an employee is receiving more permission than is necessary, and it is necessary to examine them in the context of the organisation to establish their individual risk. Risk is not a binary measure and, in this work, an approach is built using Fuzzy Logic to determine an overall risk rating, which can then be used to make a more informed decision as to whether a user is over-entitled and presenting risk to the organisation. This requires the exploratory use of establishing resource sensitivity and user trust as measures to determine a risk rating. The paper presents a generic solution, which has been implemented to perform experimental analysis on Microsoft’s New Technology File System to show how this works in practice. A simulation using expert knowledge for comparison is then performed to demonstrate how effective it is at helping the user identify potential irregular permissions.