Thursday, 4 March 2021

Android - Samsung Smart Switch // iOS Transfer Artifacts

 Recently I was trying to set up an Android device to run some testing on and I just happened to pick a Samsung this time around. I needed some sample data on it but I didn't have a lot of time to generate information. Luckily, Android has a way you can restore information from one device to another, even if that device isn't an Android. 


If you happen to be transferring over to a Google Pixel phone, Android will allow you to use the USB-C adapter to connect a USB-A to Lightning cable that has an iOS device running on the other side. I thought this was a pretty slick process and will likely be checking into it more in time to see what happens on the Pixel side. 


Since Samsung is one of the most popular device manufacturers it shouldn't surprise anyone that they are copying this functionality on their device line. In order to do this, Samsung has the user download the Samsung Smart Switch application which can also be found on the Google Play store. (Link) Samsung isn't alone on this, with OnePlus, LG, and 3rd party groups using this same functionality, but Samsung is the one we'll focus on today. 


After grabbing my iPhone test device I plugged it into the S20 I was testing out and followed the step by step process that the device had displayed on the screen. 


Samsung allowed me to select quite a bit of information including SMS/MMS, Contacts, Photos/Videos, and even Application data. So after this process, what is left behind by the Smart Switch application that could be relevant to our investigations? 


The application uses the bundleID of com.sec.android.easyMover. Looking for that in the file system, there weren't many databases that appeared there at first. Within the shared_prefs folder, there was a "smartswitch_prefs.xml" file that had some great information in it including: 

  • Source Device Type
  • Target Device Type
  • Google Account Sign-In

Within the "files" folder of the com.sec.android.easyMover application directory, there was a LOT of interesting files left behind. First off there is a folder: data\data\com.sec.android.easyMover\files\iosotgmanagerv2\
Within this folder, a Plist file can be found identifying the source device the data came from. This is the lockdown plist file that is used as part of the Trust Pairing process of iOS. 

There is a folder called SmartSwitch which also has some great data. An "iosApps.json" file will store information about iOS applications detected from the source device. 



A "requestedApps.json" is a JSON file keeping a log of the matching Android versions that will be requested from the Play Store as well as version. 




The "BrokenRestoreInfo" directory of my device had some additional interesting JSON files. The DevInfo.json file contained UDID information, model number, OS versions, Display Name, and what was asked to be backed up. 



The JobItems.JSON will let the examiner know what was able to be downloaded from the source device. 



A PHOTO folder will contain additional JSON files that contain metadata about recovered photographs from the source device. 



Another folder, SmartSwitchLog contains several log files about the transfer process. This folder also contains the most important piece of the application as well. In this source image, a DATA_0 folder was found containing the bulk of the transferred information. This folder contains a multitude of ZIP files that have the information backed up from the Source device. These files within the zips may be named in some cases the same SHA1-named structure as the files would be from within the original iOS device's iTunes-style backup. Several examples will be linked below: 

 BACKUP DATA: 
DATA_0_BACKUP_INFO.zip --> Contains the Manifest.db for the iTunes-style backup which will give you a listing of every file included in a backup on the source device as well as helping to decipher the SHA1 names in the recovered files. 



ALARMS: 
DATA_0_ALARM_0.zip --> Contains the file cc723e4537a6d5120fb720dda7dd18b10f3f4a97 which is the Library/Preferences/com.apple.mobiletimerd.plist from the iOS device. 
DATA_0_ALARM_1.zip --> Converted.xml: The converted version of the above Plist file. 

BOOKMARKS
DATA_0_BOOKMARK_0.zip --> Contains the file d1f062e2da26192a6625d968274bfda8d07821e4 which is the Bookmarks.db from Safari. Also contains BookMark.xml which is the converted version of this database. 

CONTACTS
DATA_0_CONTACT_0.zip --> Contains the file 31bb7ba8914766d4ba40d6dfb6113c8b614be442 which is the AddressBook.sqlitedb from the iOS device. 
DATA_0_CONTACT_1.zip --> Converted VCard (.vcf) data from the above database. 

MEMO / NOTES
DATA_0_MEMO_0.zip --> Contains the file ca3bc056d4da0bbf88b5fb3be254f3b7147e639c which is the notes.sqlite and the file 4f98687d8ab0d6d1a371110e6b7300f6e465bef2 which is the NoteStore.sqlite database. 
DATA_0_MEMO_1.zip --> Contains a Memo.zip which has a JSON file inside it which is the converted notes data of the two above databases. 

MESSAGES
DATA_0_MESSAGE_0.zip --> Contains the file 3d0d7e5fb2ce288813306e4d4636395e047a3d28 which is the sms.db from the iOS device. 


DATA_0_MESSAGE_1.zip --> Contains several relevant files including: 
sms_restore.json - All of the SMS messages from the above database converted into a JSON file. 
mms_restore.json - All of the MMS messages from the above database converted into a JSON file. 
NOTE: iMessages are organized into the appropriate JSON above for their type either SMS/MMS. 
PART_files - Attachments recovered from the SMS/MMS/iMessage attachments. 





PHOTOS
The PHOTO folder contains information about the photographs and videos extracted from the source iOS device, but not the media itself. 

But what if you don't have a full filesystem of the device and you're stuck with just a Quick image of the data? In that case, examiners should turn to the media/0 (or emulated sdcard) directory to find the SmartSwitch directory. Within this directory under "tmp" an ENTIRE copy of the iTunes-Style backup was recovered!



Within the SmartSwitch/tmp directory there were several folders to support the transferred data. Unfortunately, not all of these kept the JSON files that were available from the data's stored information from within /data/data. Some of these folders did, such as the message_json folder containing all of the same JSON values from earlier. 

The photos/videos transferred from the source iOS device were also discovered within a folder in the emulated sdcard directory called iPhoneData. This directory contained all of the recovered documents and media items transferred over. The names from the source device were not kept in this directory and the previously discussed photo logs keep the information about how the files are renamed. 



Android is well known for duplicating data across multiple areas of the filesystem. If the SmartSwitch application is found on a subject's device, several directories should be checked for this previous device's transferred data. Some of these areas are more available to the end user than others so each directory may or may not still have data within it. 

As a wrap up and reminder, the directories that should be checked are: 

/data/data/com.sec.android.easyMover/files --> Look for the iosotgmanagerv2, SmartSwitch, and SmartSwitchLog files. Search for any DATA_0 folders for the stored .zip files containing both original source information and converted JSON data. 

/data/media/0/iPhoneData --> Contains the recovered documents and media from the iOS device (original source names NOT kept). 

/data/media/0/SmartSwitch/tmp --> Look for the original backup of the iOS device as well as the converted JSON data within the appropriately named folder. 


And that's it for this post! In the future, I definitely want to explore the same data but for an Android to Android transfer as well as exploring the Pixel version and other manufacturer's version of the same processes. 



Tuesday, 26 January 2021

Android - Roles and Permissions (Android 10/11)

 Well it's a bit since I've been able to update, so I thought I'd change that. I've been working on some new research for a class I'm building and it's been giving me a chance to deep dive into some fun stuff for both iOS and Android.  I'm usually very interested to figure out preferences, permissions, and default applications on platforms as it can help shape the user's behavioral patterns. Because of this, I want to talk about where you can go look for this information in Android as it's been shaken up a bit thanks to Android 10 and 11. 

Once place to go look for installed applications on Android is the packages.xml and packages.list files that can be found within an Android's /data/system/ directory. Using the packages.list file can allow an examiner to see what applications are installed, where the data is stored within the file system, what SDK API the application is using, and some version number information. It should be noted that when a path references /data/user/0/[package name] they're referencing the /data/data/[package name] directory as Android sets up a symbolic link between the two for the default user. Additional users will be listed out there with their own user paths.



 The packages.xml file will list out all of the packages but also the permissions that each package is using. In addition to this, it will also store some good information about where the application is being stored (the apk file) as well as the installing package. If the package is com.android.vending then it came from the Google Play store. However, applications that are side loaded by another method such as ADB or downloading from the web will have a different "installer" and "installInitiator" value. 


App Installed from Google Play: 


App Installed via ADB: 


You can see above that the installer for Snapchat was com.android.vending while the Magisk Manager was installed by com.google.android.packageinstaller. 


The packages.xml file also shows which permissions have been granted by the user and requested by the application. This can help an examiner determine what functions an application may have. In addition to the package information here, there are other files which track permissions referred to as runtime permissions. For more information on the runtime-permissions.xml file and what gets stored in there I'm going to refer you over to Josh Hickman's blog on it here: https://thebinaryhick.blog/2021/01/26/androids-dangerous-permissions/. Josh was awesome in helping me test some stuff out with this. Definitely go read Josh's post on the runtime-permissions file as these are dangerous permissions that are very crucial to an investigation. 


In addition to the runtime-permissions.xml file there is also a roles.xml file. The roles.xml file is part of the Role Manager that Android added with version 10. This allows you as an examiner to figure out what the default set application is for specific functions in Android. Previously this was divided out into the settings_global, setttings_secure, and settings_system.xml files within the /data/system/users/#/ directory. The roles.xml file can be crucial in determining what application has been set by the user (or system) to perform a function, thus telling an examiner where to go look for data. Here's an example from a Samsung phone running Android 10. This file can be found in /data/system/users/0/


You can see above that most of the Samsung default applications have replaced some of the core Android functions for tasks like SMS, Dialer, Launcher, and Browser. So on this device, in addition to looking for SMS data in the standard mmssms.db file, we would need to look in the /data/data/com.samsung.android.messaging/databases directory for information. 


In Android 11, the path of the roles.xml and runtime-permissions.xml have moved. Now, they can be found in the /data/misc_de/0/apexdata/com.android.permission. If a device ran Android 10 and was then upgraded to 11, files will be present in both locations but the new location will be used for changes made after the shift to 11. By comparing the two, examiners may be able to learn historical information.


 


Curious, why ever would a calculator application need access to Camera and to write to external storage? Yeah, I think we all know the answer here. The crucial takeaway is that these permissions are NOT stored as part of the packages.xml file. 



Because these files are stored in the directories they are, they should be available even in BFU style images where only the DE (device encrypted) containers have been decrypted. 

Understanding permissions and preferences can be crucial to learning how a target behaved on their device as well trying to key in on other places where data may be duplicated. Understanding the permissions applications request can help an examiner find things that might seem out of the ordinary. In addition, anyone doing Malware investigations on Android devices should pay special attention to several of the files mentioned here to figure out where applications came from, what permissions they requested, and if they've taken over functions of the device for the user. 

Big thanks to both Josh Hickman @josh_hickman1 and Kevin Pagano @KevinPagano3 for helping me test this stuff!

Monday, 28 September 2020

iOS - Tracking Bundle IDs for Containers, Shared Containers, and Plugins

 In iOS, one of the more vexing things I've found when working through data or helping a student with questions usually comes back to tracking what application is responsible for putting data in a specific place. With some of the fantastic work done by others including Alexis Brignoni (link here) on the ApplicationState.db as part of the FrontBoard directory, it has always become one of my first go-to spots to build a "treasure map" of applications to deal with those annoying AppGUIDs that Apple assigns each app on a device. These annoying things I speak of can be found when you're looking for data in: 

/private/var/mobile/Containers/Data/Application


Luckily, most tools will parse out the ApplicationState.db and map each one of these unique IDs to the application which is stored within. 


Great! So much easier to go and figure out what apps are living where. However sometimes you stumble upon a file of interest within a folder and you're left with the task of matching the directory path to this database. Maybe you're in a situation where you're working with just the raw image and limited access to tools as well. How can we find the app's bundleID from within a directory already? 

Within the application data path, at the root there should be a file ".com.apple.mobile_container_manager.metadata.plist" which seems to be same name in each application directory. This information will contain keys that contain the bundleID of the application which is great if you're in a pinch and don't want to jump back and forth. 

The more interesting thing is what happens when you do a search for this file across your iOS device. If you do, you'll see that the .com.apple.mobile_container_manager.metadata.plist file appears in a lot of places including: 

  • /private/var/containers/Bundle/Application/APPGUID/
  • /private/var/containers/Shared/SystemGroup/APPGUID/
  • /private/var/containers/Data/System/APPGUID/
  • /private/var/mobile/Containers/Shared/AppGroup/APPGUID/
  • /private/var/mobile/Containers/Data/Application/APPGUID [duh]
  • /private/var/mobile/Containers/Data/InternalDaemon/APPGUID/
  • /private/var/mobile/Containers/Data/PluginKitPlugin/APPGUID/


Whoa. That's a lot more places for us to explore to make our treasure map. So what is this file anyway? First, let's talk about Sandboxing. Apple heavily utilities sandboxing in iOS. This is to prevent applications from getting access to data they're not supposed to have access to. Each application is given its own sandbox to play in and only that area to play in. This plist file allows us to see what sandbox we're in and who owns that sandbox from an application perspective. Using this information, we can break down a little bit more of this path information above to figure out why certain apps may be keeping data in a location. 


/private/var/containers/Bundle/Application/

This directory is where the .app lives on the device. There's some additional data we can track here about the application itself and who downloaded it onto the device. Along with the .app, there's an iTunesMetadata and BundleMetadata plist file that can list out information such as when the application was downloaded, what version of the app was downloaded, and what AppleID actually downloaded it. 



/private/var/containers/Shared/SystemGroup/

This directory is similar to the one above, but speaks to core applications of the iOS device. There's less information in here but still a .plist file that can reveal what system application is responsible for the container. 

/private/var/containers/Data/System/

Again, similar to the directory above, but these seemed to be system apps that didn't want to share information between core applications. Again, less relevant information except for the bundleID who owns the container. 

/private/var/mobile/Containers/Shared/AppGroup/

Now this is where the REAL fun begins! I mentioned sandboxing earlier. Apple says that applications are not allowed to share information without requesting it through official channels first. In order to share information, application developers can assign a "group" to their application. According to Apple's developer information, these groups can then share data between each other. You may have also seen these in backup-style images that are listed as "AppDomainGroup-group.bundleID" instead of the "AppDomain-com.bundle.ID" structure. I have often used this path when I couldn't find the data I was looking for in the main Application Data path. 

Now for the downside. The ApplicationState.db doesn't contain information about this path. The upside? Each application's "Shared/AppGroup" directory will have one of our .com.apple.mobile_container_manager.metadata.plist files! Woohoo! To make it even better, Alexis Brignoni has built support into iLeapp in order to list out out all of these files from this directory allowing us to match the contents of the file to the path it lives in. [Get iLeapp here]

An application may also have more than one folder in this path. A couple of examples would be the Dropbox application that over 4 different containers here and the Spark email app which had 2. More importantly, some applications may keep all of their relevant data here instead of the /private/var/mobile/Containers/Application/Data/ directory. An example of this would be the Spark email application (iTunes web link) which chooses to store all of its relevant databases within the /private/var/mobile/Containers/Shared/AppGroup/ directory structure instead of the more common /private/var/mobile/Containers/Application/Data/ directory structure. [Other notable examples of this include WhatsApp and Signal]




/private/var/mobile/Containers/Application/Data

The place where we're supposed to look for app data. Well understood and documented. Just, not where we always end up wanting to look after all. 

/private/var/mobile/Containers/Application/InternalDaemon

In my test devices these appeared to be Apple services (or internal daemons, obviously) that could be tracked using the same .com.apple.mobile_container_manager_metadata.plist files. 

/private/var/mobile/Containers/Application/PluginKitPlugin/

I've had two situations recently that I've been assisting students with to understand where crucial data to their cases has wound up within this area. Populating exact matching data here is difficult but a few situations arose in which I was able to track a good bit of information. Because Apple is allowing applications to use plugins to tie together (think of the Giphy keyboard, my personal favorite), these plugins can keep data within this directory structure. One test case was to figure out why a bunch of illicit videos were showing up within a specific directory. By using the .com.apple.mobile_container_manager.metadata.plist file, the analyst was able to figure out what plugin was helping to put data in this directory and what bundleID the plugin belonged to. In this case, it was tied to com.apple.mobileslideshow's PhotoMessagesApp.


Note: com.apple.mobileslideshow is the Photos application on iOS. 

Now that we know what plugin and what application the directory belongs to, we can then go out and try to generate data to prove how this information gets in here. In my example, I used the photo picker plugin within iMessage and then modified the video directly within that plugin without launching the original com.apple.mobileslideshow application. Using KnowledgeC, you can see in the following screenshots that when these files were created within the PluginKitPlugin/APPGUID/ directory structure that the MobileSMS application and other plugins overlap. 


Other plugins such as 'com.apple.mobileslideshow.photo-picker' have come up in other investigations but sometimes it's difficult to populate these directories without KnowledgeC or PowerLog to go on. By at least understanding the owning BundleID, we can start to understand possibilities for how data got where it is. 

Now we have a better way to build out our own treasure maps as well as now knowing that .com.apple.mobile_container_manager.metadata.plist files are typically going to provide the "X" that marks the spot. 

Wednesday, 23 September 2020

iOS 14 - Tracking App Clips in iOS 14

 iOS 14 brought a couple of new features I've been wanting to test. In past years I've evaluated Android's "Instant Apps" feature and of course when Apple added this with iOS 14's App Clips I had to see what was being stored. 

So what are App Clips anyway? For that I'll direct you over to Apple's website here. Apple's App Clips are mini-versions of applications that a user can quickly download and interact with without installing the full version of the app. These App Clips can be distributed to users in several ways from being embedded into web pages, NFC tags, QR codes, or even by using apps like Messages or Maps. 


When a user gets a notification they can download an App Clip it'll open up on their device after a brief download screen. From there they can interact with a minimal version of the application. Depending on the app, you'll get access to features the developers want you to have with obviously a big and constant incentive to download the full version of the application. Below are some screenshots of the process of finding an available App Clip (one via the Maps app and one via Safari), installing them, and using them. 


Hm, Panera sounds good for dinner, but I don't have the app. So instead, I can just use the Maps app to direct me to the Panera App Clip instead. 


The App Clip will appear as though it's running. It will generate its own KTX snapshots and be a running process within the device. 


However, you won't find the app listed on the Home Screen or iOS 14's new App Library either. Even if you accidentally close it you can't just use Spotlight to launch it again. 


Here's the Kontax Cam app. You can launch it directly from the website. 


All tested App Clip downloads look just like this. A blurry background and the text will slowly fill up with white as a progress bar. 


Most App Clips will constantly display a notification encouraging you to get the full version of the app. Here, you can see the app would allow me to take a photo but not actually save or do anything with it until I did. App Clips will transition your information to the full version of the app if you download it. 


So where can we find out what App Clips are even installed? There's some forensic artifacts to discuss but on a live-running device we can go to the Settings -> App Clips page to see the clips that are currently installed on our device. You can also click on each app clip to see the permissions that have been granted to that specific App Clip as well like Camera access or Geolocation access. You can also use the "Remove All App Clips" to get rid of them from your device. 

NOTE: According to Apple's statement under that "Learn More..." they say that data associated with the app clip is deleted after 10 days of non-use. Clips are automatically deleted after 30 days of non-use. 

One More Note: The above graphics were from my iPhone, while the screenshots and research below were done on a separate iPad device running iOS14/iPadOS14. Mostly because this is currently the only iOS14 device in which I can get a full filesystem image at the time of this writing. 

From a forensic image perspective, what can we track for these applications? It's going to depend on your level of access, as always. I noticed that from within my testing that NONE of the App Clips I tested (there were about 4 in this device as the number of apps using these are still limited) kept data within an iTunes-style backup. I was able to track that certain clips were used by using both iTunes-style backups and SysDiagnoseLog data, but not the data itself. 

Tracking the Data -  Installation and Storage

The first step in tracking these app clips is to see what the user has installed. Because of the way iOS tracks installed applications depending on your image type, we have to look in multiple placed. 

Info.plist / Manifest.plist - In a quick image, both the info.plist and manifest.plist file did not have any App Clips listed. 


ApplicationState.db - In both the quick and full image, the ApplicationState.db file tracked the clips being installed as well as their "true" path. In my testing, none of the App Clips data or bundles were in the iTunes-style backup. 




Each App Clip had the same bundle ID of the full application only with .clip added to the end of it. 

mobile_installation.log.0 - Full image or found within the sysdiganoselogs. These logs can show the applications that are installed and could go to show App Clips that are used and then deleted over time.


 Tracking the Data - Usage

Outside of tracking what App Clips are actually installed, the same methodology we would apply for regular apps seem to apply. The ApplicationState.db and mobile_instalation_log.0 data points gave us the right directories for finding anything that's stored. This will obviously change from app to app, but should at least point us in the right direction. Other standard artifacts that would be used to map when the apps are used like KnowledgeC and PowerLog are tracking these App Clips just the same. 


I did notice that right before the App Clip was triggered in KnowledgeC the service "com.apple.ClipViewService" would pop right before while the App Clip is being loaded. 

Tracking information for the "ClipServices" led me down to a new path found only in full filesystem image: private\var\mobile\Library\com.apple.ClipServices.clipserviced\. The ClipData.db database found here stores information about the App Clips installed and permissions approved by the end user. 

A quick and easy SQLite query for parsing this information is: 
SELECT "bundle_id", 
"user_notification_consent", 
"location_confirmation_consent",
"allows_location_confirmation_after_launch",
datetime('2001-01-01', "last_user_notification_request_time" || ' seconds') AS Last_Notification_Request_Time,
datetime('2001-01-01', "last_version_check_time" || ' seconds') AS Last_Version_Check_Time,
datetime('2001-01-01', "last_install_time" || ' seconds') AS Last_Install_Time,
"parent_app_name",
"parent_app_store_url"
from app_clips; 





App Clips can ask special permissions that may extend beyond the standard TCC.db. This may prove to be another prime location to find this data. 

As more applications release their App Clip variants, I expect this database to grow in importance. I would expect that using KnowledgeC and PowerLog can help show how these app clips are getting onto the device. Only time will tell how important these clips are to investigations, but at least we have a good way of tracking them on the device!

Thursday, 17 September 2020

iOS 14 - Message Mentions and Threading

 After diving into some basic stuff of iOS 14 in the last post I wanted to see if I could track any of the new features to iMessage. Both inline replies to messages and mentions didn't really stand out to me when I was doing initial testing because the schema looked mostly the same. Sneaky Apple decided to imbed some of this data as well as create some new columns at the far end of our tables. 


Overall the table structure of iOS 14's sms.db looks the same. Diving into the message table we can see where the new stuff comes into play. 


Mentions: 

In order to see who specifically is mentioned when someone does an direct mention of another user, Apple is embedding this data into the BLOB found in the attributedBody column of the messages table. In the below screenshot you can see when a user is mentioned the text is a little bit bolder than the regular message text. Incoming mentions also appear in a different color. 


Now in order to provide a mention, once you start typing the name of someone in the chat (it doesn't show up for people not in the chat) it will change the color of the name in your text box. If you click on this, it will give you a small pop up that allows to make sure you have the right contact selected. 


Now as far as tracking this information, I thought maybe it would be embedded inside the same binary plist file that tracks if a message was Sent with Siri in iOS 13. Nope. Instead, we have to turn to the attributedBody blob. 

Here we can see a mention of a number (in this case this was an outgoing mention in my test data). 


And next the mention of an AppleID. (This one was an incoming mention)



Inline Replies: 

Apple also added the ability to do inline replies to iOS 14 iMessages. In order to make these backwards compatible if they're sent to an iOS 13 user they'll still appear as just a normal message. For iOS 14, there are some new columns added to the end of the messages table which can help us. Here's how it looks to the end user.


In order to see what messages were replies, and what messages they were replying to, we can use the GUID and thread_originator_guid columns in the messages table. Each message is assigned a guid when it is saved in the database. Messages that are replies, will have a value in the thread originator guid which tie them together. It should be noted that the "reply_to_guid" will still help track the order in which the messages were meant to display in and could be different from the actual inline reply guids.



In the above screenshot you can see that both the "Did you get it yet?" and "I got it shortly after we talked" messages are replies to the guid beginning with 830EEC08 which is the message "Still waiting" found in rowID 12. 

As I said in my original iOS 14 blog post (here), I'm sure we'll be finding things as we all go along so keep watching this space as more stuff gets dropped!