1. Challenges

2. Android’s Access Control
The lack of isolations between apps
Malware can make use of IPC (Inter-Process Communication) ways like Binder to attack benign APPs.
Static permissions
Permissions can neither be dynamically modified by users, nor be adaptable to circumstances (like locations).
Poor security for underlying system components
Low-level protections or mechanisms such as SEAndroid, root permission, database, etc can still be compromised.

3. Thoughts and Solutions

4. Android’s Access Control
Security Isolations
Samsung and KAIST proposed the concepts of Rich Execution Environment (REE) and Trusted Execution Environment (TEE), security channels have been established to guarantee secure communication between untrusted code and trusted code. (SeCReT, NDSS’15)
ZJU proposed a lightweight virtualization solution for Android devices called Condroid ( This work improves the Cell work proposed in SOSP’11 by modifying framework layer instead of kernel layer for better compatibility with Android. (LXC, IEEE TC, Jan 2015)
Condroid Architecture
Architecture of REE and TEE

5. Android’s Access Control
Dynamic Permissions
Purdue University proposed Context-Based Access Control (CBAC) model. It can be used to express different policies under multiple contexts (time and location). This work is a support for Bring Your Own Device (BYOD) scenario. (CBAC, TDSC, Mar 2015)
PSU proposed SemaDroid, A privacy-aware sensor management framework for Smartphones. This work introduces Quality of Service (QoS) theory and presents fine-grained restrictions on sensor permissions. (SemaDroid, CODASPY’15)
CBAC Model
SemaDroid Architecture

6. Android’s Access Control
Security Enhancement for Android Components
SamSung Research America and NCSU proposed EASEAndroid, an automatic analysis platform for SEAndroid policy based on Large-Scale Semi-Supervised Learning (LS3L). It can be used to assist security experts to refine existing access control policies. (EASEAndroid, USENIX Security’15)
University of Bergamo in Italy proposed SESQLite, a security enhancement for SQLite based on SELinux. Security labels are enforced on tables, rows and columns to achieve better granularity of Mandatory Access Control (MAC). The policy for SESQLite is compatible with SEAndroid’s and can be integrated with the latter. (SESQLite, ACSAC’15)
EASEAndroid Architecture
SESQLite Architecture Overview