SIM PIN Challenge
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Back in 2005 I was at a presentation by a SIM manufacturer when the presentation turned to CHV (Card Holder Verification), the correct technical term for PIN used for SIM Cards.
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The presentation had reached the part "Verifying the CHV" and went on to record:
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~ To verify PIN, the verifyCHV APDU is used....
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A0 20 00 CHVNum 08 PINValue
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~ The message sent from the phone to the SIM in order to check your PIN number 1111, is:
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A0 20 00 01 08 313131FFFFFFFF
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This all seemed normal until three slides later when the presentation started to discuss "File Structure after personalization" and displayed the graphics starting with the Master File (MF) and under which there were five Elementary Files (EF). The graphics displayed in the presentation were text book style when discussing MF and EFs, except for this presentation the manufacturer had gone as far as to identify two particular CHV EFs; one of which was 3F00 - EF_CHV1 0000.
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.So does that mean a particular EF under the MF in SIM with a logical address 3F00 0000 is always going to be the CHV1 file and would the raw data from that EF reveal a user's PIN number?
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Below are raw data extracts from three phases of SIM cards - Phase 1, Phase 2 and Phase 3 (2+) and harvested from the Master File (MF) 3F00 and an unnamed EF immediately under the MF with an address 3F00 0000.
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Your challenge, if you are interested, is to examine the raw data and corroborate whether the data reveals a user's CHV1 (PIN number) or not.
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To help, you may want to check the GSM SIM card standard GSM 11.11 to comprehend file structure, formatting and coding etc for elementary files and to learn what the standard has to say about CHV/PIN.
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As forensic investigators you shouldn't need the 'carrot and stick' approach to get you to undertake this challenge because I know how much you all love your work and can't get enough of it and that should be reward enough :-). However, the first person who posts the correct answer at Forensic Focus , I am sure we can sort out some sort of prize:
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http://www.forensicfocus.com/index.php?name=Forums&file=viewtopic&t=3349
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However, there are some rules (there is always something like this):
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1) In your answer it should contain identification to a document or weblink that supports the answer (the document/weblink must be traceable and not based on "something somebody told you"). This will be checked before any prize is awarded.
2) Challenge closes 15th February 2009.
3) I wont be giving the answer, because I do not want everyone just to sit back and think they can wait for my reply.
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GOOD LUCK
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PHASE 1 SIM Card
3F00
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Response: 00 00 1A 47 3F 00 00 00 F1 F4 44 13 15 83 02 03 04 00 82 8A 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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Allocated memory :1A47File ID :3F00
Type of file :MFNumber of DF : 2
Number of EF : 3 Number of CHV's : 4
CHV1(PIN1) :Disabled
CHV1(PIN1) Status :2 Tries left
CHV1(PIN1) Status :10 Tries left
CHV1(PIN1) Status :0 Tries left
CHV1(PIN1) Status :0 Tries left
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3F00:0000
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Response: 00 00 00 18 00 00 00 00 FF FF FF 13 06 00 00 02 01 00 00 0A FF
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File ID :0000
Type of file :RFU
Structure of file :Transparent
File Size :0018
Read Access :CHV (PIN) 15
Write Access :CHV (PIN) 15
Increase Access :CHV (PIN) 15
Rehabilitate :CHV (PIN) 15
Invalidate Access :CHV (PIN) 15
File Status :Not Invalidated
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Phase 2 SIM Card
3F00
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Response: 00 00 63 9C 3F 00 01 FF FF FF FF 01 0E 93 02 07 02 00 83 8A 00 00 00 00 83 00 FF
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Allocated memory :639C
File ID :3F00
Type of file :MF
Number of DF : 2
Number of EF : 7
Number of CHV's : 2
CHV1(PIN1) :Disabled
CHV1(PIN1) Status :3 Tries left
CHV1(PIN1) Status :10 Tries left
CHV1(PIN1) Status :0 Tries left
CHV1(PIN1) Status :0 Tries left
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3F00:0000
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Response: 00 00 00 12 00 00 04 00 FA FF FF 01 02 00 00
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File ID :0000
Type of file :EF
Structure of file :Transparent
File Size :0012
Read Access :CHV (PIN) 15
Write Access :CHV (PIN) 10
Increase Access :CHV (PIN) 15
Rehabilitate :CHV (PIN) 15
Invalidate Access :CHV (PIN) 15
File Status :Not Invalidated
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Phase 3 (2+) SIM Card
3F00
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Response: 00 00 00 01 3F 00 01 00 00 00 00 00 09 81 04 12 0A 00 83 8A 83 8A
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Allocated memory :0001
File ID :3F00
Type of file :MF
Number of DF : 4
Number of EF : 18
Number of CHV's : 10
CHV1(PIN1) :Disabled
CHV1(PIN1) Status :3 Tries left
CHV1(PIN1) Status :10 Tries left
CHV1(PIN1) Status :3 Tries left
CHV1(PIN1) Status :10 Tries left
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3F00:0000
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Response: 00 00 00 17 00 00 04 00 FB FF FF 01 02 00 00
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File ID :0000
Type of file :EF
Structure of file :Transparent
File Size :0017
Read Access :CHV (PIN) 15
Write Access :CHV (PIN) 11
Increase Access :CHV (PIN) 15
Rehabilitate :CHV (PIN) 15
Invalidate Access :CHV (PIN) 15
File Status :Not Invalidated
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