Investigating User Privacy in Android Ad Libraries

Recent years have witnessed incredible growth in the popularity and prevalence of smart phones. A flourishing mobile application market has evolved to provide users with additional functionality such as interacting with social networks, games, and more. Mobile applications may have a direct purchasing cost or be free but ad-supported. Unlike in-browser ads, the privacy implications of ads in Android applications has not been thoroughly explored. We start by comparing the similarities and differences of in-browser ads and in-app ads. We examine the effect on user privacy of thirteen popular Android ad providers by reviewing their use of permissions. Worryingly, several ad libraries checked for permissions beyond the required and optional ones listed in their documentation, including dangerous permissions like CAMERA, WRITE CALENDAR and WRITE CONTACTS. Further, we discover the insecure use of Android’s JavaScript extension mechanism in several ad libraries. We identify fields in ad requests for private user information and confirm their presence in network data obtained from a tier-1 network provider. We also show that users can be tracked by a network sniffer across ad providers and by an ad provider across applications. Finally, we discuss several possible solutions to the privacy issues identified above.

[1]  Markus Jakobsson,et al.  Badvertisements: Stealthy Click-Fraud with Unwitting Accessories , 2006, J. Digit. Forensic Pract..

[2]  P. Francis,et al.  Privad: Rearchitecting Online Advertising for Privacy , 2009 .

[3]  David S. Evans.  The Online Advertising Industry: Economics, Evolution, and Privacy , 2009 .

[4]  Yoshiharu Ishikawa,et al.  Anonymizing user location and profile information for privacy-aware mobile services , 2010, LBSN '10.

[5]  Helen Nissenbaum,et al.  Adnostic: Privacy Preserving Targeted Advertising , 2010, NDSS.

[6]  Hamed Haddadi,et al.  MobiAd: private and scalable mobile advertising , 2010, MobiArch '10.

[7]  Byung-Gon Chun,et al.  TaintDroid: An Information-Flow Tracking System for Realtime Privacy Monitoring on Smartphones , 2010, OSDI.

[8]  Paul C. van Oorschot,et al.  A methodology for empirical analysis of permission-based security models and its application to android , 2010, CCS '10.

[9]  Shashi Shekhar,et al.  QUIRE: Lightweight Provenance for Smart Phone Operating Systems , 2011, USENIX Security Symposium.

[10]  Heng Yin,et al.  Attacks on WebView in the Android system , 2011, ACSAC '11.

[11]  Lorrie Faith Cranor,et al.  When are users comfortable sharing locations with advertisers? , 2011, CHI.

[12]  Avi Goldfarb,et al.  Privacy Regulation and Online Advertising , 2010, Manag. Sci..

[13]  Avi Goldfarb,et al.  Online Display Advertising: Targeting and Obtrusiveness , 2011, Mark. Sci..

[14]  Christopher Krügel,et al.  Understanding fraudulent activities in online ad exchanges , 2011, IMC '11.

[15]  Hassan Artail,et al.  An on-demand mobile advertising system that protects source privacy using interest aggregation , 2011, 2011 IEEE 7th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob).

[16]  Seungyeop Han,et al.  These aren't the droids you're looking for: retrofitting android to protect data from imperious applications , 2011, CCS '11.

[17]  Steve Hanna,et al.  Android permissions demystified , 2011, CCS '11.

[18]  Jennifer King,et al.  Privacy: is there an app for that? , 2011, SOUPS.

[19]  David A. Wagner,et al.  AdDroid: privilege separation for applications and advertisers in Android , 2012, ASIACCS '12.

[20]  Xuxian Jiang,et al.  Unsafe exposure analysis of mobile in-app advertisements , 2012, WISEC '12.

[21]  Shashi Shekhar,et al.  AdSplit: Separating Smartphone Advertising from Applications , 2012, USENIX Security Symposium.

[22]  Hao Chen,et al.  AndroidLeaks: Automatically Detecting Potential Privacy Leaks in Android Applications on a Large Scale , 2012, TRUST.