Permission re-delegation: attacks and defenses

摘要: Modern browsers and smartphone operating systems treat applications as mutually untrusting, potentially malicious principals. Applications are (1) isolated except for explicit IPC or inter-application communication channels (2) unprivileged by default, requiring user permission additional privileges. Although supports useful collaboration, it also introduces the risk of redelegation. Permission re-delegation occurs when an application with permissions performs a privileged task without permissions. This undermines requirement that approve each application's access to devices data. We discuss demonstrate its launching real-world attacks on Android system applications; several vulnerabilities have been confirmed bugs. We possible ways address redelegation present Inspection, new OS mechanism defending against re-delegation. Inspection prevents opportunities reducing after receives from less application. implemented browser Android, we show found in applications.