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Mobile Phone and SIM card cloning

  2. Warning. MOBILE & SIM CLONING2 These slide is only for education purpose. No SIM card or Mobile phone is cloned . My purpose is to draw attention towards security vulnerabilities in GSM and mobile communication.
  3. MOBILE & SIM CLONING Contents 1. Introduction 2. What is phone or SIM cloning? 3. What is the Purpose of cloning? 4. Requirements for cloning 5. How cell phone cloning is done? 6. Mobile station 7. Base Transceiver station 8. GSM authentication 9. COMP 128 and A5 10. Process of SIM cloning 11. Man in the middle attack 12. How to know your phone or SIM is cloned? 13. Preventive measures 14. What can be done by cloned SIM or phone? 15. References 3
  4. 1. INTRODUCTION MOBILE & SIM CLONING Nearly 1 billion telecom subscriber worldwide. Estimated that worldwide mobile phone fraud will reach $40 billion dollars soon. US Law enforcement agents have found that 80% of drug dealers arrested in US using cloned mobile phones. Pablo Escobar the top Columbian drug dealer was tracked down by monitoring his mobile phone activity. 4
  5. 2. What is cell phone or SIM cloning? MOBILE & SIM CLONING Copying the identity of one phone or SIM to another phone or SIM. The bill for usage goes to legitimate subscriber. 5
  6. 3. What is the Purpose of cloning? MOBILE & SIM CLONING Making fraudulent phone calls Getting owner messages. Using internet on owners bill Using phone to commit a crime. Getting personal information of owner. Listening owner calls. To tease anybody etc. 6
  7. 4. Requirements for phone cloning? MOBILE & SIM CLONING ESN ( Electronic Serial Number): Unique number Loaded when phone is manufactured. Cannot be changed or tempered. MIN ( Mobile Identification number) Every subscriber provides a MIN to its user. It is a unique number. ESN/MIN pairs can be discovered in several ways: Sniffing the cellular phone ( need physical access to phone) Hacking cellular company database7
  8. 5. How cell cloning is done? MOBILE & SIM CLONING Cloning involves modifying or replacing the EPROM in the phone with a new chip which would allow you to configure an ESN ( Electronic serial number) via a software (eg. PATAGONIA). Then you would also have to change MIN (Mobile identification number) by the same software. When we had successfully changed the ESN/MIN pair, your phone is an effective clone of other phone.[2] 8
  9. 6. MOBILE STATION MOBILE & SIM CLONING Consist of Mobile Equipment and SIM. Mobile equipment has IMEI – International Mobile Equipment Identity 9
  10. SIM(Subscriber Identity module) MOBILE & SIM CLONING SIM provides details printed on the surface : Name of the Network Provider Unique ID Number Personal Identification Number (PIN) 4 digit code set at point of manufacture that can be changed by the Subscriber. Usually 3 attempts before SIM is blocked Pin Unblocking Key (PUK) 8 digit code set by manufacturer Maximum 10 attempts before SIM is permanently blocked 10
  11. MOBILE & SIM CLONING KI (Subscriber identification key) Size is 128 bits (16 bytes) loaded in SIM hardware can not be changed (read only). Goal Authenticate subscriber to network Create a session key IMSI (International mobile subscriber identity) Unique for every subscriber. [3] 11 SIM Contd…
  12. 7. Base Transceiver Station (BTS) MOBILE & SIM CLONING The network element which handles the radio interface to the mobile station. The BTS is the radio equipment (transceivers and antennas) needed to service each cell in the network. 12
  13. 8. GSM authentication MOBILE & SIM CLONING13
  14. GSM authentication Contd….. MOBILE & SIM CLONING The base station sends a 16 byte random number say RAND. The SIM card get this RAND and uses the KI(secret number) to feed to A3A8 (COMP-128) whose output is a 12 byte long number say OUTPUT. OUTPUT is split into two parts , upper 4 bytes is called as SRES(authentication key) and lower 8 byte as Kc (encryption key). SRES is send to Base Transceiver Station as Authentication response. Where the operator uses the same algorithm because he knows our KI and match the SRES then we are authenticated. The Kc is sent to Mobile which is used as encryption key for A5 algorithm.[1] 14
  15. 9. COMP – 128 and A5 algorithms MOBILE & SIM CLONING COMP 128 algorithm is used to generate the Encryption key (Kc) and Authentication key (SRES). There are three versions of COMP algorithms In V1 last and second last byte of Kc is 0x00. In V2 last byte of Kc is 0x00. In V3 bytes may be anything between 0x00 to 0xFF which is the most secured one. A5 algorithm is used to encrypt the voice over-the-air communication.[1] 15
  16. 10. SIM Cloning Process MOBILE & SIM CLONING Things required : Blank SIM card ,SIM Card Reader and a software to generate the content for blank SIM. (Can be bought from , etc.) Step 1: Remove the SIM from your phone, place it in the SIM card reader. Step 2 :Read the KI code and IMSI Read SIM card for KI and IMSI using software Once KI and IMSI is found ,save your cracked SIM information to a .dat file. 16
  17. SIM Cloning Process contd…….. MOBILE & SIM CLONING Disadvantage: Need physical access to the SIM card for at least 30 minutes. Step 3: Writing to blank card Put the blank card in the reader. Select write to SIM. Select .dat file you saved before. It will take about 10 minutes to write it. your card is cloned. If you try to make 2 calls at the same time, one will go through, the other will say call failed, and both phones will get the same messages, text and voice, and both will receive the same calls, but only one can talk at a time. [4] 17
  18. 11. MAN IN THE MIDDLE attack MOBILE & SIM CLONING In GSM only subscriber is authenticated with the network but there is no way by which a network can be authenticated. Anybody can not get whether the network is reliable or not. It is possible for the network to order the MS to switch on and off encryption at times of high loading. This signal can be spoofed using a man-in-the-middle attack. 18
  19. MOBILE & SIM CLONING Operator BTSLegitimate Subscriber Man-in-the- middle 1. Attempt toregister usingencryption 3. Authenticates Spoofing BTS Spoofing MS 2. Passesontheregistrationrequest 4. Passesonauthentication 5. Dialsanumber 6. RequestsMSswitchoff encryption 7. Encryptsthenpassesonthecall request 8. Call proceedswit MIMeavesdropping 19
  20. 12. How to know your phone or SIM is cloned? MOBILE & SIM CLONING Frequent wrong number phone calls to your phone. Difficulty in placing outgoing calls. Difficulty in retrieving voice mail messages. Incoming call constantly receiving busy signals. Increased bill amount. 20
  21. 13. Preventive measures MOBILE & SIM CLONING Always set a PIN in the SIM card. Always set up security code in the phone. Switch to 3G SIM card which are more secured then 2G. 21
  22. 15. References MOBILE & SIM CLONING Research papers [1] Security in the GSM network Marcin Olawski [2] CDG Document 138 Version 0.34 CDMA Development Group, 575 Anton Boulevard, Suite 560 Costa Mesa, California 92626 [3] Design of a Routing Mechanism to Provide Multiple Mobile Network Service on a Single SIM Card Boobalan. P, Krishna. P, Udhayakumar. P, Santhosh. A Websites [4] sim.html [5] 22