Contaminating Evidence SIX

The original question (in Part ONE) I believe was asked by someone starting out in mobile forensics. I tend to find it is easier to start with the 2G technology [SIM Application CLA (0xA0) / 2G context], which is still predominant in certain countries; although market research shows 2G falls below 30% globally by 2020.

Furthermore, law enforcement and security still seize and find 2G SIM cards (globally speaking) associated with criminal activity - drug dealing, SIMboxing, trafficking, etc. - so any observations to assist examination may help improve outcomes, assist generate "quality in work" but without expending large quantities of capital.

Equally, with 3G and 4G SIM cards the examiner can still SELECT and ReadBinary etc. re: GSM Access. Also, it is helpful to let examiners see basic script commands and responses as the basic commands can still be issued under [USIM Application CLA (0x00)]:

SelectUSIMApplication
Select 6F07
ReadBinary

To make the following a little more interesting than merely showing a screen image of USIM Application returning the SIM Card's IMSI, does the mobile network IMSI match the network to which the IMSI was last latched?

For privacy and security purposes the IMSI has been obscured, however it is confirmed the IMSI for this discussion is a subscriber to the EE network. As an examiner you may consider looking to the last network and location the subscriber was camped.

SelectUSIMApplication
Select 6F7E (e.g. location area)
ReadBinary

SelectUSIMApplication
Select 6F73 (packet switched location area)
ReadBinary

Observations, at first instance: the LOCI and PSLOCI screens reveal that the subscriber's account has been latched to the T-Mobile network; not EE or Orange network. Who would provide feedback to the investigating office on what that means? Both of these screens show "updated" for location and routing area, yet the P-TMSI Signature Value has been unchanged FFFFFF. What significance, if any, would that import into interpreting the data?

The key point of using commands and getting responses can assist an examiner refine searches made to (U)SIM and the (U)ICC and also respond to "time-is-of-the-essence" requests in cases of device seizure at the point a trafficker is stopped and searched. Combining precise information searches can help examiner's do this.

Moreover, with enhanced scripting and script variables we can do so much more and a matter that will be considered in another blog discussion post/s soon regarding examination, evidence and validation:

==========
ContinueOnBadStatus
Select 3F00
Select 7F20
Select 6F07
If (GoodStatus = True)
{
 ReadBinary
 If (GoodStatus = True)
 Pass
}
Fail
===========
===========
Select 3F00
Select 7F10
Select 6F3A
Set $recNum = 1
While ($recNum <= $totalRecords)
{
 ReadRecord $recNum
 Increment $recNum
}
===========
===========
$count
$recordNumber
$data
$alphatag
$bitmask
===========

The tool USIM Commander is a SIM evaluation and programming tool available from Quantaq Ltd and can be found here: http://www.quantaq.com/products/simtools/

Hope you find this helpful.


Contaminating Evidence ONE  - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-one.html
Contaminating Evidence TWO - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-two.html
Contaminating Evidence THREE  - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-three.html
Contaminating Evidence FOUR - http://trewmte.blogspot.co.uk/2017/05/contaminating-evidence-four.html 
Contaminating Evidence FIVE - http://trewmte.blogspot.co.uk/2017/05/contaminating-evidence-five.html

Contaminating Evidence FIVE

To refresh, these discussions (links at foot of this article) originated because someone asked a question e.g. should I put a seized damaged SIM card into a seized mobile phone (handset), where both items have been found placed into the same Exhibit bag? The discussions have been to highlight helpful observations about what can be involved and learning the lesson to keep a damaged SIM card separate from the handset and conduct tests independently from combined forensic suites; hence the need for Test A Damaged SIM Card SOP.

Yes, you can run a test single APDU (application protocol data unit) command to select particular data from a SIM card, as you can run a script containing multiple test APDU commands. For example, what follows is an example of multiple APDU command to SELECT and GET RESPONSE  from the SIM card requesting the SIM's IMSI (international mobile subscriber identity). Invariably, investigating officers and security may only require just that little piece of information; and whether extracted and harvested from a working SIM or a damaged SIM. Where a damaged SIM Card is involved it wont be clear at the initial examination stage whether (a) the SIM will respond to any test or fully-blown image? and (b) if it does, could there be only chance to retrieve any data from it (the card)?

APDU Commands
We know that the standards identify commands as follows and therefore these would most likely assist the examiner when reading the SOP. Remember in part FOUR it referred to the SOP should assist examiners by identifying the short form title and clause. So here is one exercise you can do now. Go and download ETSI GSM11.11 (Release R1999) and 3GPP TS 31.102 latest release and identify the short form title and clauses relevant to the APDU commands below:

- Select
- VerifyCHV
- ReadBinary
- ReadRecord
- UpdateBinary
- UpdateRecord
- Status

Test APDU - IMSI Request
The next step is to select and chosen the statements needed to issue commands for the SIM card to reveal the IMSI:

- 2GMode
- Select 3F00
- Select 7F20
- Select 6F07
- ReadBinary 

USIM Commander GUI Image

The IMSI has been doctored in the above image for privacy and security reasons. However, the three windows panes above illustrate how to validate commands issued to a damaged SIM card. The left pane shows the commands. the top right pane shows the status and harvested data of the commands issued. And the bottom right pane confirms the translated APDU trace and the Raw APDU trace. Thus proving the process and procedure the examiner adopted and applied during testing. This information can then be logged into the examiner's Contemporaneous Notes. 

Training and Discovery
Before jumping into conducting the tests, training and exposure to different types of SIM cards and their conditions should be the first priority. Even the best APDU scripters make mistakes. The screen images that follow illustrate mistake and correction (can you find the mistake?) and following that the importance of the learning curve an examiner needs, which is only possible base upon discovery using training SIM cards to see what might be revealed.

 

 

 

Examiner need to be encouraged to extend search investigation beyond the template. The images below, identifies CHV1 and CHV2 discovery might reveal. This discovery helps examiners to uncover if unknown CHV1 and CHV2 can be revealed.



 

Contaminating Evidence ONE  - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-one.html
Contaminating Evidence TWO - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-two.html
Contaminating Evidence THREE  - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-
three.html
Contaminating Evidence FOUR - http://trewmte.blogspot.co.uk/2017/05/contaminating-evidence-four.html 

Contaminating Evidence FOUR

In the last discussion it referred to APDU (application protocol data unit) - the communications unit between the SIM card reader and the SIM card. It also mentioned that APDU are set out in the Standards. There is some more information on this you may find helpful. The Test A Damaged SIM Card SOP could include a removal of doubt (ROD)technique. The purpose of this ROD technique assists the examiner's comprehension from the outset of the 5-Ws rule of thumb:

Who - the examiner
What - testing across the interface
Where - between the DUT and the Test Tool
When - as directed by the laboratory Good Practice Guide (GPG)
Why - to avoid contamination of evidence

To aid that process the SOP could reference the procedure with the inclusion of the relevant standard numbering and title, also directing the reader to a specific clause. It is irrelevant for the purposes of testing to ask an examiner to remember something s/he was taught some time back. A permanent record in a document of direction and advice instructing the examiner is needed. Practices and procedures should not be left to guesswork. As the old adage states " it is not knowledge you need to hold-on to in your head as this is recorded in books; it is the skills and experiences you should remember." A permanent record, then, is a reference book. The skills and experiences developed through use and discovery are those essential requirements to maintain and evolve the SOP, which when recorded then goes on to become knowledge.

ISO/IEC 7816

In Part ONE it referred to ISO/IEC 7816-1. That is because it is the starting point that identifies other 7618-parts. Here we need to look at ISO/IEC7816-3. The above image show the specific section to be discussed. But for the sake of manner and form let us use a page within the SOP identifying Standards and Text applicable to it (the SOP and its procedures and tests therein):

Standard Title:
============
INTERNATIONAL STANDARD ISO/IEC 7816-3 Third edition 2006-11-01
Identification cards — Integrated circuit cards — Part 3: Cards with contacts — Electrical interface and transmission protocols
============

However a short form identity for the relevant Standard and clause/s are required. This is placed at the end of paragraph following the written procedure or test (otherwise any procedure and test would be verbosely overloaded with repetition of a Title like the above).

Short Form Identity:
=============
(ISO7816-3 (cl12.1.1)) 
=============

Note that apart from going to a separate document (e.g. relevant Standard and clause) everything that an examiner should require should be in the SOP. The reasoning behind that has many responses but to highlight: (a) avoids an examiner reading wrong, incorrect or out of date material; (b) excessive amounts of information can confuse; (c) examiners will be testing, but prior to tests and following tests contemporaneous notes should be made which could be excessively lengthy if the SOP references are not used....and so on.

It can also be helpful to produce GUI screen images and samples of APDU so that the examiner is equally guided to know what to look for in any trace file output for validation purposes.

USIM Detective

Dependent upon the (U)SIM/(U)ICC hardware reader and software (system) used it is important that the examiner does not end up using another system to perform the tests. If a different system is used a new SOP should be created for every system in use. If support is needed for that then an example can be given here. The above screen image shows the ADPU commands and responses in the USIM Detective trace file. However, Simspy2 trace file output is different:

Simspy2

  
This might suggest the commands and responses that are output should still be identical? No, not all commands and responses will be identical. Worse still, if the examiner starts quoting one system in a report and the data used is in fact from another system. An example of this is Simspy2 and USIM Detective both issue commands and responses that can acquire different data. Both issue commands to fetch data from memory locations that are not specified in the standards. This does not suggest they are wrong, merely they offer different traced evidence.

Unless each Lab produces its own system then the market forces of commercially or freely available systems will be the pool from which systems are obtained. The more tools the better, but budgets can dictate a system to be used, although in reality obtaining free software should not present a problem. Purchasing a commercial system, it should be possible to fully scrutinised data captured and that the system has the back-up evidence to produce a trace file output containing the commands and responses where validation is needed.

Validation requires confirmed interpretation of commands issued and as mention in previous discussion seeking guidance from the standards can save an awful lot of time and assists avoiding guesswork:

GSM11.11

Lastly, but still relevant to Test A Damaged SIM Card SOP, it should be made clear in the SOP that the standard referred to identifies the "interface" as referenced in the standard. In this discussion ISO7816-3 confirms the "electrical interface" and the transmission protocols used. However, as (U)SIM cards emerge with additional capabilities in the (U)SIM or at the (U)ICC level it is important to record additional interfaces significant to the method and process evidence is captured:

Contaminating Evidence ONE  - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-one.html

Contaminating Evidence TWO - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-two.html

Contaminating Evidence THREE  - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-three.html

Contaminating Evidence THREE

Parts ONE and TWO can be found here for those who haven't followed the discussion so far:

Contaminating Evidence ONE  - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-one.html

Contaminating Evidence TWO - http://trewmte.blogspot.co.uk/2017/04/contaminating-evidence-two.html

I have received enquiries asking for references how to test a damaged SIM card is working or not? This is not a case of simply sticking the damaged SIM cards into a SIM reader and using software to see what content is returned from various data files.

Lab Managers, Section Leaders and Examiners need to define the aims and objectives for testing damaged SIM cards. This should be on the basis of the Test A Damaged SIM Card SOP. The use of general statements in these discussions are not aimed to tell you what to do or how to write your examination processes and procedures. It offers, hopefully, helpful suggestions on basic materials needed to develop and evolve SOP. The following materials could serve as a foundation template with which to prepare and guide the preparation of headings and descriptions; themselves used to define how tests should be conducted.

Avoiding a discussion about how to top and tail a SOP document, nor discuss the merits of aims and ambitions, Do's and Don't (so to speak) and so on, the focus will highlight the relevance of "interface". The first question to ask is who's interface? There are a few to deal with when examining a damaged SIM card:

1) The hardware interface of the damaged SIM card
2) The software interface of the damaged SIM card
3) The probes of hardware of the examining tool
4) The software of the examining tool

Because there are many internal communications entities on a SIM card it can be thought of in terms as having it own mini-network. Here is an image of communications network where at certain points interception is required to deal with e.g. cyber attacks.




We can see network elements as being defined as entities of the network and we need to get to those entities to discover what is inside (content). We therefore require defining the object identifiers for 'path-to-content', so perhaps creating an identifier tree that illustrates the reference points of interest can help you do that?

Unlike a full communications network, which it is not realistic to attempt to obtain an image compared to a device; the SIM card's mini-network in a device can be imaged. Identifying elements and entities in the SIM card's mini-network examiners can look to the following standards:

ISO/IEC 7816-1
GSM 11.11; 11.12; 11.14; 11.17; 11.18
3GPP 31.120;31.121
ETSI TS.102230

To illustrate how the standards can be used to create a standard operating procedure (SOP) in the photo below I have identified physical, electrical, electronic and logical elements to be considered by combing the details taking the test reference identifiers in GSM 11.17 and overlaid them to GSM 11.11 reference points.  These are known as the SIM test groups.

Germane and relevant is the interface processes and procedures chosen have a 'forensic' requirement that the device's content should not be altered by our actions (so to speak). "Human Intervention and Tools (HIT) need to demonstrate that their interaction with the device does not change any data. All tests carried out using an examination tool should also be carried out on the basis of understanding any limitations of the tool."

So when it comes to testing the damaged SIM card we have background knowledge, but does that mean we have to create new software utilities and hardware for testing to see if the card can be imaged using a SIM card reading software? There is a huge range of physical hardware readers out there that are compliant with the Standard's physical, etc. interface requirements. To support that proposition examiners can use hardware such as SCR331 etc. Moreover, there is the utility PC/SC diagnostic tool. I chose this utility because it was available back in 2002-2003 and a popular tool for testing GSM SIM cards.

The purpose of using a test utility on the damaged SIM card is that you do not want to run a fully blown image process on the damaged card because you do not know the extent of the damage inside to its micro-computer electronic circuits (do you think that should be stated in your SOP?). PC/SC diagnostic tool enables testing only the boot-up of the card and to return its ATR (answer-to-reset) and other system parameters.  As the test does not penetrate the Master File (MF) and elementary files (EF) the tool only works with the shell and wont read and return content such as the EFICCID or EFIMSI and so on.

When conducting a test read of the damaged card the results returned will need to be saved. PC/SC diagnostic tool provides for saving the test report. Identifying the name of the report is optional, but when training it is perhaps a good idea to get into the practice of identifying the report from the SIM Serial Number (SSN) recorded on the face of the card. In the photo below I have simply used filename ICCID so as not to identify a test card or a case exhibit.

The initial report that is saved will be a plaintext .txt file. To prevent loss or alteration of that file convert the .txt file to a working document (.pdf).

Examiners essentially need to be aware how the test tool works. It writes APDU (application protocol data unit) - the communications unit between the SIM card reader and the SIM card. The APDU are set out in the Standards.

When preparing your damaged SIM card SOP some key information to have considered and confirmed are:

a) Does the tool permanently write to the card?
b) If so, and working at the shell, where would that be discovered, if at all?
c) Can a write blocker be used?
d) What can be learned from the ATR and parameters?    

If the test results obtained are good this detail can be used in the decision-making process whether or not to create a cloned test card. Remember to enter a caveat in the SOP and to the client that internal damage cannot be seen and therefore any image extracted thereafter might only be on a one-shot basis.

Remember: photographs and well documented contemporaneous notes are essential here. Make the effort to record details so that you don't have to struggle trying to remember what the device was like or what you did.

Metrology - USB part 2

Continuing with the discussion relating to Metrology and Universal Serial Bus (USB) cables.

Metrology - http://trewmte.blogspot.co.uk/2015/05/metrology.html
In the first discussion it raised the observations iso9001 has been mentioned and this standard provides a useful guide on record keeping. In most cases users take for granted that the cable/lead/plug is ok and just swap it out if it is deemed not working? Simple questions:

1) Is there a cable/lead tester on the market?
2) What results can be obtained?
3) How to determine output results?
4) Compare manufacturing guidelines for MTTF and MTBF?
5) Can the results scrutinised be improved?
6) Can a minimum standard be achieved.

Metrology - USB part 1 - http://trewmte.blogspot.co.uk/2015/06/metrology-usb-part-1.html
Later the discussion raised the notion that smartphones, tablets and other devices fitting the description Size-Scaled Digital Technology (SSDT) using USB physical connectivity provides for the simplest of examination DUT illustrations e.g. the combination of three separate entities involved in inter-connection during an examination:

1) DUT (the target device (SSDT) containing suspected evidence
2) The physical medium (USB) to carry the source data to the examination tool
3) The examination tool (ET) used to extract and harvest evidence

And ended with the point that the discussion started out by referring to the physical medium USB to carry the source data from the DUT to the examination tool (ET). The relevance of doing so is that if the examiner eliminates the medium as the cause for failure or corrupted evidence then the logical conundrum that remains, is the DUT at fault, is the ET at fault or are both DUT/ET together faulty?

In order to eliminate the USB cable's involvement in the acquisition process as the source of causing corrupted data or inducing faults into the DUT requires expanding the investigation of what is known about USB tolerances or identified faults.

Mechanical Failures

Types of USB connector left to right (ruler in centimetres): micro-B plug, UC-E6 proprietary (non-USB) plug, mini-B plug, standard-A receptacle (upside down), standard-A plug, standard-B plug

The procedure required to dissect and strip back a USB plug from its cable. In itself, there is nothing special in this task being performed other than for revelation purposes to allow observations of what is happening underneath the main moulded cable covering, due to the fact that the human eye does not possess x-ray vision. This USB cable was chosen as it had visible signs of wear and tear at the USB plug end that connects to the device (DUT) and charging of a DUT was known to be intermittent.

The USB cable was terminated at either end with a mini-B plug and standard-A plug. The photo below shows the mini-B plug end has been dissected and stripped back.

 The standard coloured wiring is expressed as:

Pin 1		VCC (+5 V, red wire)
Pin 2		Data− (white wire)
Pin 3		Data+ (green wire)
Pin 4		Ground (black wire)

It was noticeable from a study of the separate coloured internal wire covers - Green, Red, Black and White ( For a quick reference source refer to https://en.wikipedia.org/wiki/USB. ) - that the Red wire cover was in fact a Pink in colour with deterioration (more brittle, easy to pull off covering) than the other coloured coverings.

Given that the mini-B plug is the end that is connected into the DUT raises concerns as to whether the wear and tear could cause damage to the DUT, too. As the Red(Pink) coloured cover concerns the power V_CC (+5 V, red wire) it is not difficult to speculate the potential for damage or failure and that on the balance of probability (at one of the end of the scale) the quality assurance programme should have identified this as a problem or issue to be addressed, (and at the other end of the scale) that beyond reasonable doubt the quality control processes should have removed this physical medium (USB cable) from the pool of tools/devices that could be used during an examination process.

The sampling rates for conducted Vbus and Vcc etc tests can be deduced from the USB standards. Full USB compliance test equipment maybe expensive for those who are trading as a one-man business. There are some simple test rigs out there which require the use of a digital multimeter and test cables that may offer a lower cost solution worth investigating.

One such rig is USB Tester from Fried Circuits http://friedcircuits.us/docs/usb-tester

Another rig from the same source is USB Tester and Phone Charging http://friedcircuits.us/docs/usb-tester-and-phone-charging/

Inexpensive rigs like these should not be a problem but it is essential to carefully document their use in your QA procedures and their requirement to be calibrated.

There are still numerous matters to discuss that have been identified regarding Metrology and USB, which shall be published shortly. The total sum of these discussion Parts build eventually to an identified set of criteria that examiners may wish to apply for QA purposes to reduce or remove the medium USB as having an adverse impact during data acquisition between a DUT and the ET.

Considering Clone Test SIM Card Tools

Considering Clone Test SIM Card Tools

There have been a few mentions about clone test Sim Cards at this blog raising observations as to possible issues that may be useful to know.  

Yet further observations examiners may find useful to consider are whether it is necessary for a cloned test SIM Card tool to produce identical files, structure and format for every clone test card produced or whether the make/model of handset can influence e.g. the number of files etc necessary to gain access to a handset's memory? Cust_Files pre-generated on a cloned test card should be included or excluded from consideration regarding the number of GSM/3GPP EFs identified on a cloned test card? The importance, if any, of the evolution in a clone test card's development?

Below are two screen dumps, following examination using just one (U)SIM Card Reader, from two different clone test SIM Cards supplied by different manufacturer with their tools that provide a useful visual indicator when placed in context with the above observations. The observations above and the images below are not published to suggest a problem with a particular clone test SIM Card or tool. The observations are for the purpose should two different examiners use two different clone test SIM Cards and tools to generate evidence which one would be more pertinent for use when accessing memory on a particular handset etc?      

Considering Clone Test SIM Card Tools

Considering Clone Test SIM Card Tools

There have been a few mentions about clone test Sim Cards at this blog raising observations as to possible issues that may be useful to know.  

http://trewmte.blogspot.co.uk/2012/10/to-clone-or-not-to-clone.html
http://trewmte.blogspot.co.uk/2008/11/cloning-test-sim-cards.html

Yet further observations examiners may find useful to consider are whether it is necessary for a cloned test SIM Card tool to produce identical files, structure and format for every clone test card produced or whether the make/model of handset can influence e.g. the number of files etc necessary to gain access to a handset's memory? Cust_Files pre-generated on a cloned test card should be included or excluded from consideration regarding the number of GSM/3GPP EFs identified on a cloned test card? The importance, if any, of the evolution in a clone test card's development?

Below are two screen dumps, following examination using just one (U)SIM Card Reader, from two different clone test SIM Cards supplied by different manufacturer with their tools that provide a useful visual indicator when placed in context with the above observations. The observations above and the images below are not published to suggest a problem with a particular clone test SIM Card or tool. The observations are for the purpose should two different examiners use two different clone test SIM Cards and tools to generate evidence which one would be more pertinent for use when accessing memory on a particular handset etc?      

Examination Techniques8: Simple Experiments2

Examination Techniques8: Simple Experiments2

Continuing the discussion to offer suggestions on ways to generate test methodologies in order that down the line it might be possible to create validation and verification processes, practices and procedures for mobile phone examination (device under test (DUT)). 

Assuming that an examiner is satisfied as to when s/he is using the appropriate tool that it will extract and harvest data from the make/model (DUT) under examination, there will still be the prior query what exactly is this tool communicating to the DUT? For instance, considering logical data as opposed to physical data, does the tool intended for use provide an "output log" that contains the communications (commands) sent to the DUT (e.g. APDU or AT+ etc etc) so that the examiner:

- can corroborate what is being instructed to the DUT when that tool is applied to it?
- comprehend are the responses (data) received from the DUT to be expected or are the data incomplete?
- Should the data be incomplete, is that because the commands are incorrect in their instructions which data are to be extracted or is it because the handset has not stored any further data other than that data returned in response to the command sent?

The objective of this simple experiment is to observe the content of any harvested logical data so that when dealing with physical (deleted) data recovery an examiner can start to build a template, from known logical data samplings, in order to apprehend some understanding of any deleted data that has been recovered as to what maybe there and what maybe missing.

Previous discussions relevant to this topic:
Examination Techniques6: Simple Experiments - http://trewmte.blogspot.co.uk/2012/03/examination-techniques6-simple.html

Examination Techniques5: Validation and Verification - http://trewmte.blogspot.co.uk/2012/03/examination-techniques5-validation-and.html

External links:
http://www.forensicfocus.com/Forums/viewtopic/t=8879/

Blinking Ice Cream Sandwich (ICS)

Blinking Ice Cream Sandwich (ICS)

Security issue concerns raised about Samsung's 'Face Unlock' has received a boost in the new OS upgrade release of ICS as it is reported to contain an additional security feature requiring the user to 'blink', in addition to existing security already in place, according to global.samsungtomorrow. So for those who thought using a photo of the user for 'Face Unlock' now could require, additionally, a moving image of the user blinking. Whether that requires the genuine user to blink naturally or forced blinking is unclear. Certainly something else to consider when dealing with a DUT with ICS OS during mobile phone examination.

Examination Techniques3: Blackberry Bold

Examination Techniques3: Blackberry Bold

Examiners may have noticed that the internet is flooded with secret or hack codes that may be entered into a handset and a brief description of the code's purpose. Every make and model seems to have its own codes. One code that has been doing the rounds since 2010 is the Blackberry Bold code for ' Display cause of PDP reject ' relevant to GPRS. Below is list of sample entry codes posted on the internet. As you can see there appears to be some variation in the way the code is expressed it should be entered into a Blackberry:

ALT+JKVV @ Home Screen. Display cause of PDP reject
http://newestblackberryfreeware.com/blackberry-tips-and-tricks/blackberry-secret-codes/

ALT-JKVV Home Screen Display cause of PDP reject
http://forum.mintywhite.com/viewtopic.php?f=9&t=790

ALT-JKVV Home Screen Display cause of PDP reject
http://forums.crackberry.com/archive/index.php?t-78665.html

ALT+JKVV @ Home Screen. Display cause of PDP reject
http://www.xusermanual.com/all-tags/blackberry-bold-3-secret-codes

It is recommended that examiners may wish to consider researching the use of the codes on test handsets prior to conducting 'live' examination on the evidential DUT.

However, a second matter that was apparent from the internet postings that there was no assistance given to the reader or, for that matter, an examiner as to the interpretation of the information (data) that would be displayed on the screen of the DUT as a value or a cause that would be relevant to it (the value).

In order to understand the meaning of the data relevant to ' Display cause of PDP reject ' examiners should at first instance review 3GPP TS24008 / GSM 0408 in order to understand the relevance of PDP with respect to 'Activate PDP Context Reject State ' when it is On and the value given in an ' Activate PDP Context Reject SM Cause '.

Below are several tables compiled with content relevant to PDP reject values and their causes. Whilst I have reviewed standards and other sources to seek agreement of the values and causes, you may wish to check for yourself the accuracy of the information recorded in the tables. The 3GPP/GSM standards have been identified above and to conduct simple Binary/Hex/Decimal conversion readers may wish to visit an online calculator website similar to the one at the following link http://easycalculation.com/binary-converter.php.

GMM Cause Information Element



SM Cause Information Element



SM Cause Information Element on GTP protocol



Whilst the values and causes in the tables above have been identified there is still additional information that the standards identify relevant to each of them. Having said that, being able to investigate these values/causes and trace them to the GSM MS / WCDMA UE and to the network is quite helpful, particularly when dealing with blacklisted handsets or invalid IMSIs. Additionally, the values and causes provide a useful guide when conducting live tests for GPRS cell site analysis.