Showing posts with label Elementary Files. Show all posts
Showing posts with label Elementary Files. Show all posts

Sunday, October 06, 2013

(U)ICC/(U)SIM Script Commands and Responses

(U)ICC/(U)SIM 3F00 7F10 6F4A

3GPP UICC/USIM script selecting Master File, Dedicated File and Elementary File





















GSM ICC/SIM script selecting Master File, Dedicated File and Elementary File






























Reason for script test : defining an examination procedure to isolate and test a single elementary file; determine the EF's status, file structure, coding etc; conrroborate the ability of the (U)ICC/(U)SIM to action responses from commands sent to card; provide corroborating evidence of commands sent to the card to demonstrate evidential integrity (transparency of practices and procedures); testing the examination card reader is functioning correctly; QA procedures. 

Script examination tool used : USIM Commander - http://www.quantaq.com/usimcommander.htm

Relevant Core Diplomas:-

Aims : MTEB Diploma for Mobile Evidence QA and Evidence Handling - Mobile Telephone Diploma Core CQAE1

Objectives : Device Maintenance and Calibration; Examination Procedure

Aims :  MTEB Diploma for SIM and USIM Technology Examination - Mobile Telephone
Diploma Core CSUT2

Objectives : Your understanding of roles and responsibilities and the importance of
appropriate practices and procedures for SIM and USIM Technology
Examination for acquiring evidence.

Reference Standards :
GSM11.11/3GPP TS51.011/3GPP TS31.102,
GSM11.12,
GSM11.17/3GPP TS51.017/3GPP TS31.120/3GPP TS31.121/3GPP TS31.122,
GSM11.18/3GPP31.101,

EU MTEB Diploma Student Note : Remember to check with ETSI Standards e.g. TS102.221 etc

US MTEB Diploma Student Note : Diploma Students remember to check e.g. C.S0065-0 v1.0, C.S0074-0 v1.0, C.S0074-A v1.0, N.S0009-0 v1.0, S.R0095-0 v1.0 etc

Generically speaking, apart from GSMA and 3GPP, there is also 3GPP2 which also includes ARIB, CCSA, TIA TTA, TTC that all have conditions that can impact/influence results on (U)ICC/(U)SIM.

The discussion under (U)ICC/(U)SIM Script Commands and Responses is one of a number that will appear here to assist Diploma students with their course work.

The latest MTEB Diploma Modules Guide MTEdipl 2.2 can be downloaded here:
https://dl.dropboxusercontent.com/u/84491783/MTEdipl%202.2.pdf


Sunday, September 13, 2009

BCCH data uncovered

BCCH data uncovered
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The data found in the elementary file broadcast control channel (EFBCCH) 7F20:6F74 / 7F21:6F74 can provide useful data relating to a geographical radio area when combined with location area information data.

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Method for translating BCCH information data. The question is, is the translation below to find the BCCH frequencies correct and what have I not mentioned below? You will need copies of GSM11.11, GSM03.03, GSM04.08 as well as understanding coding schemes.
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FIGURE 1 What the Standard states:
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FIGURE 2 What that means:
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FIGURE 3 Harvested data from a Orange SIM Card read:
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FIGURE 4 Translating the hex output to binary:
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FIGURE 5 Converting to decimal digits which translates again and corresponds to GSM assigned uplink/downlink frequencies:
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BCCH Frequencies (ARFCN)
761 765 766 774 781 782 786 787 789 790 797 799 801 803 806 813 816 825 828 829 838 846 847 849 869
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FIGURE 6 Corroborating the conversion using another tool:
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More on Cell Site Analysis: http://cellsiteanalysis.blogspot.com

Friday, May 15, 2009

Undercover Officer Down, how might SIM Access Control Class help? Part 1

PART 1: Undercover Officer Down, how might SIM Access Control Class help?
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The following is a scenario created to help examiners and experts know more about how to determine what data in SIM/USIM elementary files can mean and to appreciate what is required to be understood before examining SIM/USIM and giving evidence. Computer forensics has made a significant contribution to data recovery that can be used for harvesting data from mobile telephones and SIM cards, however data recovery is only one element of mobile telephone evidence and is not ‘the evidence’ to be considered in isolation to everything else.
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Moreover, an examiner and an expert are expected to usefully advise with respect to investigations where data obtained from mobile telephones and SIMs/USIMs are involved, so, here to, this scenario will hopefully open examiners' and experts' eyes to new ways of considering data. What the law of evidence wants to know is, provided the data recovered is not a problem, what does the data actually mean and how should it be interpreted.
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Scenario
An undercover officer working has infiltrated a criminal organisation involved in drugs and people trafficking. The undercover officer needs to keep details and seek answers without blowing his cover. The situation is always life threatening. The officer is required to report back by mobile phone to Control every 7-14 days.
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PC0001 on patrol in the Shopping Mall sees a known drug dealer in the doorway of a Supermarket with an unknown IC1 female handing over a package. PC0001 calls and waits for back up before approaching. A stop and search is then conducted using the appropriate procedures under PACE 1984. A quantity of drugs is found, large bundle of money, along with two mobile telephones which were all subsequently put into evidential containers and the two individuals are carted off in the wagon to the local nick.
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The alleged crime of drug selling (given the quantity seized) is fairly low down the scale and the money found was £1,780.00, but compared with other crimes wasn’t high and so priority won’t be given to this case over other cases in the system. The mobile phones are sent away for examination. The person assigned to deal with the examination of the mobile telephone and SIM card conducts a quick level examination for subscriber details, mobile telephone number, SIM serial number/ICCID, phonebook and text messages. Before starting examining the mobile telephone the examiner becomes ill and doesn’t complete the work.
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The examination would need to be passed to another examiner who would have to start from scratch as the next examiner could not possibly give evidence about someone else’s work for the new examiner would have no knowledge about the previous examination. By chance the new examiner chosen for the work had just come back from Greg Smith’s TrewMTE SIM Card training course where he had undergone deep level training into being a professional examiner and taught about ethical working practices, understanding the symbiotic relation with other mobile telephone devices and network elements, technical standards, working practices and SIM Card examination and data investigation etc (well alright, but it is only a modest promotion about me).
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The new examiner conducted a fresh examination, starting with the SIM Card. Having been trained to look for evidence of activity and indicators about the potential user of the SIM card, the new examiner immediately contacted the Senior Officer where PC0001 was stationed. The new examiner, having been trained to identify certain data and corroborate the finding with reference material to ensure the meaning of the data, explained to the Senior Officer that he was examining a mobile telephone SIM Card that may belong to someone in the Security Services and that if he, at the local level, was examining this SIM then it could mean there was a man [undercover] down in the field?
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Asked why the new examiner might suspect this, he referred to the recent training he had had and had identified from a mandatory data file in the SIM Card an elementary file titled EFACC (Access Control Class). The SIM had recorded Access Class 12 which is referenced as “Security Services”. The examiner also informed the Senior Officer that he had acquired from the SIM the subscriber details and mobile telephone number but was not authorised to access personal details. The examiner also mentioned that as ex-British Army he had field experience and should “intel” suggest there may be a “man down” that he would rely on all efforts to be made to rescue him, he therefore considered the user of the SIM (being examined) would equally rely on the same.
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The Senior Officer took the details and immediately set in motion a priority search. The details the new examiner had given to the Senior Officer had proven correct and were linked to an officer on field ops. It transpired the office had not been in contact for 14 days. Because of the work involved MI5 were called in for their superior network of intelligence and, given the nature of the criminal organisation, every school boys heroes were sent in, the SAS, to conduct ground surveillance, attack, capture and rescue. The undercover officer was rescued, badly beaten, bleeding and barely alive, but alive nonetheless.
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To clear up some loose ends to this scenario: How did the drug dealer come to be in possession of the undercover officer's mobile phone? The undercover officer had been rumbled by the gang and when running away, before the gang captured him, he had thrown it away and working on the long shot he hoped that someone would find it and hand it in. The drug dealer had found it, assumed it had been dropped by a passer-by and considered it could provide anonymity for drug dealing. There is a separate story about other evidence the mobile tied to the drug dealer, but this scenario is about saving an important life.
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So what can be learned from the above scenario and what facts are known:
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a) that the examiner as fact needs proper training to know what data can be significant
b) that as a statement of fact there is an elementary file in SIM called EFACC (Access Control Class)
c) that as a statement of fact the elementary file EFACC (Access Control Class) can be assigned to a User with an Access Class 12 assigned to “Security Services”
d) the examiner should know the limitations of the tools s/he works with before using them
e) the examiner to have the tools that actually reveal the information that is significant
f) that a proper and full examination of a SIM is an absolute requirement rather than merely the examiner conducting a dumbed-down check, only looking at certain data sets
g) that checking the findings immediately following a SIM read is essential
h) to communicate straightaway of the potential for life threatening situations or national security
i) that “priority” check means “speed and instantly” and not manyarna
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In part 2 it will identify the full 16 Access Classes, look at Class 12 technical elements for Access Control Class, how it works, its uses and its limitations. What will become abundantly clear, if Part 1 and Part 2 are only dealing with Access Class 12 what can be learned about all the other Access Classes? More importantly, why has proper checking about Access Control Class and other EFs in SIM Cards not become standard practice?

Monday, February 02, 2009

SIM PIN Challenge 2

SIM PIN Challenge 2
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A reminder that this challenge ends on the 15th February 2009:
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http://trewmte.blogspot.com/2009/01/sim-pin-challenge.html
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No pressure here guys, but we have had the first written response to the SIM PIN Challenge from a Challenge Entrant who has just started in mobile telephone forensics. This Challenge should therefore be a walk in the park for all you mobile phone and computer forensic examiners who have given evidence about SIM Cards in Court.
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As a brief history about SIM Cards, the requirement for *Personal Identity Number (PIN) to be available in a SIM Card is defined by way of the GSM Standard GSM11.11. Moreover, GSM11.11 v3 1995 standard and onwards can be downloaded free of charge. So at least we know there is over 13 years of technical knowledge about SIM Card PIN that is traceable. Furthermore, there are other standards that are used to test for allocation and activation of PIN and the mandated execution of the function between the mobile phone and SIM Card.
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*Do remember that PIN is only used because it is comon language now, but has been made obsolete from the standards and replaced by CHV (Card Holder Verification).
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Finally, many ten of thousands of SIM Cards have been examined and their evidence, along with examiners' testimonies/experts' opinions, have been presented in criminal proceedings at Court for well over a decade. A large number of the SIM Cards presented for examination had PIN enabled, thus understanding the fundamental operation of PIN is vital to forensic investigation understanding and the evidence presented about it.
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I have sent copies of this Challenge and MOBILE FORENSICS AND EVIDENCE DEGREES/CHALLENGE (see weblink at the end of this discussion) to the following who have the responsibility for: innovation, universities and skills; and regulation of forensic sciences:
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Rt Hon John Denham Secretary of State for the
Department of Innovation, Universities and Skills (DIUS)
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Mr Andrew Rennison UK Forensic Science Regulator
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MOBILE FORENSICS AND EVIDENCE DEGREES/CHALLENGE

Thursday, January 08, 2009

SIM PIN Challenge

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
----------------------------------------
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
----------------------------------------
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
----------------------------------------
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
----------------------------------------
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
----------------------------------------
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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