Enabling the Ciphering Indicator on Android

Authors

  • Felician Alecu Bucharest Academy of Economic Studies
  • Paul Pocatilu Bucharest Academy of Economic Studies

Keywords:

GSM encryption, IMSI catcher, A5, Ciphering Indicator, SIM, AT Commands

Abstract

This paper exemplifies the use of AT commands to retrieve (and eventually override) the ciphering indicator status on Android by directly communicating with the phone modem. Curiously, his indicator is disabled by default both at operating system level and SIM card settings. By turning it on, the mobile handset will inform the user each time the communication becomes unencrypted, so a proper decision could be made just in time.

Author Biographies

Felician Alecu, Bucharest Academy of Economic Studies

Economic Informatics Department

Paul Pocatilu, Bucharest Academy of Economic Studies

Economic Informatics and Cybernetics Department

References

Android Ciphering Issue, available at: https://code.google.com/p/android/issues/detail?id=5353

The GSM Standard, available at: http://www.sans.org/reading-room/whitepapers/telephone/gsm-standard-an-overview-security-317

K. Paget, Practical Cellphone Spying, available at: http://www.tombom.co.uk/blog/?p=262

Forcing 3G only on Android, available at: http://siliconstation.com/how-to-force-android-only-3g/

Mobile Country Code, available at: http://en.wikipedia.org/wiki/Mobile_country_code).

U. Meyer, S. Wetze, On the Impact of GSM Encryption and Man-In-The-Middle Attacks on the Security Of Interoperating GSM/UMTS Networks, 15th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 2004. PIMRC 2004. (Volume: 4), pp. 2876 – 2883

C. Toma, Future Developments in Non-Repudiation in GSM WAP Applications, Journal of Mobile, Embedded and Distributed Systems, vol. 1, no. 1, pp. 20-31, jun. 2009, available at: http://www.jmeds.eu/index.php/jmeds/article/view/Future-Developments-in-Non-Repudiation-in-GSM-WAP-Applications

I. Bosoanca, A. Vargatu, An Overview of Vertical Handoff Decision Algorithms in NGWNs and a new Scheme for Providing Optimized Performance in Heterogeneous Wireless Networks, Informatica Economică, vol. 15, no. 1/2011, pp 5-21

I. Androulidakis, D. Pylarinos, G. Kandus, Ciphering Indicator approaches and user awareness, Maejo International Journal of Science and Technology, 2012, 6(03), pp. 514-527

Ciphering Indicator – Feature Suggestions for Windows Phone, available at: http://windowsphone.uservoice.com/forums/101801-feature-suggestions/suggestions/5825108-ciphering-indicator

Centrul de presă Politia Romana – Comunicat, available at: http://www.politiaromana.ro/relatii_publice/detalii.aspx?id=16556 [12] Security consequences following the GSM encryption algorithm crack - What is the real-world risk from the cracking of the GSM encryption algorithm?, available at: http://searchsecurity.techtarget.com/answer/Security-consequences-following-the-GSM-encryption-algorithm-crack

GSM encryption code 'cracked', available at: http://www.zdnet.com/gsm-encryption-code-cracked-2062060205/

Questions about the Interception of GSM Calls, available at: http://www.cryptophone.de/en/support/faq/questions-about-the-interception-of-gsm-calls/

Android Security Overview - SIM Card Access, available at: http://source.android.com/devices/tech/security/#sim-card-access

Hayes Command Set – GSM, available at: http://en.wikipedia.org/wiki/Hayes_command_set

F. Alecu, P.Pocatilu, S. Capisizu, Interception of GSM Calls by Turning off the GSM Encryption, Proceedings of the 7th International Conference on Security for Information Technology and Communications (SECITC'14), Bucharest, Romania, June 12-13, 2014, Bucharest University of Economic Studies Press, 2014, pp. 157-163

Digital cellular telecommunications system (Phase 2+); Specification of the Subscriber Identity Module - Mobile Equipment (SIM-ME) Interface, (3GPP TS 11.11 version 8.14.0 Release 1999, ETSI TS 100 977 V8.14.0 (2007-06), available at: http://www.etsi.org/deliver/etsi_ts/100900_100999/100977/08.14.00_60/ts_100977v081400p.pdf

How to talk to the Modem with AT commands, available at http://forum.xda-developers.com/galaxy-s2/help/how-to-talk-to-modem-commands-t1471241

Downloads

Published

2014-06-30

How to Cite

Alecu, F., & Pocatilu, P. (2014). Enabling the Ciphering Indicator on Android. Journal of Mobile, Embedded and Distributed Systems, 6(2), 52-60. Retrieved from http://jmeds.eu/index.php/jmeds/article/view/Enabling_the_Ciphering_Indicator_on_Android