SplitSecond: Flexible privilege separation of Android apps

• Main Authors: LEE, Jehyun, VENKATESWARA RAJA, Akshaya Venkateswara, GAO, Debin
• Format: text
• Language: English
• Published: Institutional Knowledge at Singapore Management University 2019
• Subjects: Android security; privilege separation; process isolation; Information Security
• Online Access: https://ink.library.smu.edu.sg/sis_research/4686; https://ink.library.smu.edu.sg/context/sis_research/article/5689/viewcontent/SplitSecond_pst19_av.pdf
• Institution: Singapore Management University

Android applications have been attractive targets to attackers due to the large number of users and the sensitive information they possess. After the success of the first step of an attack exploiting a software vulnerability, the consequential damage is primarily determined by the criticality and the amount of Android permissions that a victim application has. As a countermeasure, process separation techniques that isolate potentially vulnerable components — usually native libraries — from the critical data and permissions, have been proposed. However, existing techniques offer little flexibility in the separation, e.g., with all native code being placed into one process without considering its dependency with other (Java) components and the non-empty set of permissions needed. In this paper, we propose a flexible privilege separation system, named SplitSecond, that enables selective permission separation at the granularity of Java components and native methods. SplitSecond provides safety against the attacks by restricting permissions on a user selectable isolation unit. According to our case study and experimental evaluation on a real handset with SplitSecond adopted Android OS and 100 top-ranked Android applications, 59.59% of activities, 66.8% of native methods, and 47.49% of permissions on average are flexibly splittable by SplitSecond with moderate overhead.