Xmandroid

¨ Technische Universitat Darmstadt
Center for Advanced Security Research Darmstadt

Technical Report TR-2011-04

XManDroid: A New Android Evolution to Mitigate Privilege Escalation Attacks
Sven Bugiel, Lucas Davi, Alexandra Dmitrienko, Thomas Fischer, Ahmad-Reza Sadeghi

System Security Lab Technische Universit¨t Darmstadt, Germany a

Technische Universit¨t Darmstadt a Center for Advanced Security Research Darmstadt D-64293 Darmstadt, Germany

TR-2011-04 First Revision: April 30, 2011 Last Update: June 30, 2011

XManDroid: A New Android Evolution to Mitigate Privilege Escalation Attacks
Sven Bugiel [e-mail] Lucas Davi [e-mail] Alexandra Dmitrienko [e-mail] Thomas Fischer [e-mail] Ahmad-Reza Sadeghi [e-mail] System Security Lab Center for Advanced Security Research Darmstadt (CASED) Germany

ABSTRACT
Google Android has become a popular mobile operating system which is increasingly deployed by mobile device manufactures for various platforms. Recent attacks show that Android’s permission framework is vulnerable to applicationlevel privilege escalation attacks, i.e., an application may indirectly gain privileges to perform unauthorized actions. The existing proposals for security extensions to Android’s middleware (e.g., Kirin, Saint, TaintDroid, or QUIRE) cannot fully and adequately mitigate these attacks or detect Trojans such as Soundcomber that exploit covert channels in the Android system. In this paper we present the design and implementation of XManDroid (eXtended Monitoring on Android), a security framework that extends the monitoring mechanism of Android to detect and prevent application-level privilege escalation attacks at runtime based on a systemcentric system policy. Our implementation dynamically analyzes applications’ transitive permission usage while inducing a minimal performance overhead unnoticeable for the user. Depending on system policy