Initialization vectors: 2021

Friday, December 24, 2021

Android Tor Browser Thumbnails. What?

Tor Browser investigations usually don't go beyond possible user saved bookmarks. Thanks to a find by Loicforensic@protonmail.com (no online presence) we can locate Tor Browser thumbnails of opened tabs in the following Android directories:

  • /data/data/org.torproject.torbrowser/cache/mozac_browser_thumbnails/thumbnails
  • /data/user/0/org.torproject.torbrowser/cache/mozac_browser_thumbnails/thumbnails
The thumbnail files are named in a GUID format with a .0 extension. For example: 8c7defaa-12b9-44f4-ae78-cc8850b92ab4.0

These thumbnails are in RIFF format contained in a WEBPVP8 container. 


They can be easily viewed by opening them with Chrome browser. In order to facilitate review I have made an artifact for the Android Logs Events And Protobuf Parser (ALEAPP) framework. Using the PIL library in Python we can convert the file to PNG format for easy reporting.


Here is ALEAPP's TOR Thumbnails report. The report contains the modified time, converted to PNG thumbnail, filename, and file location path.


ALEAPP can be downloaded here: https://github.com/abrignoni/ALEAPP

Thanks to Josh Hickman (https://twitter.com/josh_hickman1) for his most excellent Android 12 test image which enabled the creation of this artifact. You can get his Android 12 test image here: https://thebinaryhick.blog/2021/12/17/android-12-image-now-available/

Any questions or any comments I can be reached on twitter @AlexisBrignoni and email 4n6[at]abrignoni[dot]com.

Wednesday, July 21, 2021

vLEAPP - Vehicle Logs Events And Properties Parser

 Short version:

Take logical extractions from cars, trucks, and infotainment systems and parse them for interesting artifacts.

vLEAPP is Python 3 code and can be downloaded here:
https://github.com/abrignoni/VLEAPP

Long Version:

The need to analyze cars for digital forensic artifacts has grown recently as vehicles have smart mobile features by default. From GPS coordinates, contact databases, call logs, and even automated driving, the forensic value of these items cannot be overstated. Sadly there are not many options regarding tools to parse these data sources. vLEAPP aspires to be an open source platform the community can use to aggregate forensic artifacts found on the most mobile of data sources, cars.

This project started from Geraldine Blay's idea of being able to easily parse any car data source in a way that easily enables the backtracking of report data to source data. We decided to use the xLEAPP code base to do so.

Challenges

Dealing with cars brings a host of challenges to the examiner. Some are:

  • Data extraction.
    • In order to pull data from infotainment systems special tooling is usually needed. Many times a chip-off is required. This can be a labor intensive process that requires extensive training.
    • vLEAPP plays no role in the data extraction process.

  • Lack of standardization.
    • Different brands will have different ways of developing their navigation, infotainment, and sensor data recording systems. Sometimes there are different ways of doing these within cars and models of the same brand. It goes without saying that the digital forensics process is has to be well executed. Artifact identification and parsing automation is needed in this field.
    • Hopefully with the arrival of Google's Android Auto and Apple's CarPlay there will a more unified data source type across vehicle brands.

  • Unfamiliar file systems
    • File systems in use by cars might not be recognized by many forensic tools. The QNX file system by Blackberry is one example. Some examiners resort to carving in the hopes of getting relevant data from these nono-supported file systems. Be aware that using branded forensic tools might not help where other more traditional computing processes might. For example QNX file systems can be accessed using a Linux Ubuntu distribution. After accessing the logical files in the QNX file system you can package them all up in a zip file for analysis in any tool or by hand. The following video is a step by step process on how to do so.

Solutions

vLEAPP provides a way to report on forensic artifacts using Python in a way that abstracts the generation of HTML, KML, TSV, and SQLite reports. The examiner focuses on where the data is located and what to pull from it. vLEAPP handles the rest. Here is a video showing how it works.



If you are not familiar with Python or how to run scripts check this short video out. It will guide you from installation to script usage. Really easy and straightforward.



Conclusions

New data sources that are case relevant will continue to surface. As digital forensic examiners we will be well served to learn some coding. Alex Caithness said it best: Learn to code because every artifact exists because of code.


If you would like to learn Python from a digital forensics examiner's perspective and contribute to this or any of the other xLEAPP projects check out the following DFIR Python Study Group playlist. It will take you from knowing no Python to parsing protobuf files and SQLite databases.


Any questions or any comments I can be reached on twitter @AlexisBrignoni and email 4n6[at]abrignoni[dot]com.

Be safe. Take care.

-Brigs


Monday, May 10, 2021

CLEAPP it! - ChromeOS Logs Events And Protobuf Parser

Short version:

Process data extractions from Chromebooks using the ChromeOS Logs Events And Protobuf Parser (CLEAPP.) 

CLEAPP is made in Python 3 and can be downloaded here:
https://github.com/markmckinnon/cLeapp


 

Long version:

Until not too long ago extracting data for forensic analysis from Chromebooks seemed impossible. Thanks Daniel Dickerman's workflow we can extract data provided you have a username and password for the device.

Check out the peer-reviewed process here:
https://dfir.pubpub.org/pub/inkjsqrh/release/1

Thanks to Magnet Forensics the process has been automated and now its implementation is available as a free software tool called the Magnet Chromebook Acquisition Assistant. 

You can do it!!

To get the free tool go here:

https://www.magnetforensics.com/resources/magnet-chromebook-acquisition-assistant/

Now what?

So now you have an awesome extraction from the device. You will receive a file named extracted.tgz.

extracted.tgz

What do you do with it? How can you dig into the contents? Use CLEAPP for it. You can get CLEAPP here: https://github.com/markmckinnon/cLeapp

Two step process:

  1. Extract the tgz file.
  2. Select the extracted data location with CLEAPP and press process. 
Simple!!! 

This project is Mark McKinnon's brainchild and it is based on the Android Logs Events And Protobuf Parser community project. ALEAPP can be found here:
https://github.com/abrignoni/ALEAPP

Currently CLEAPP parses 38 artifact categories. The project wouldn't be what it is without the contributions from Alex Caithness and Ryan Benson. Thank you so much!

Thank you gentlepeople <3

Installation

If you are familiar with how iLEAPP of ALEAPP works then you already know how to use CLEAPP. These projects are done in python. If you are not familiar with how to run python scripts just follow the steps in the following video.


You can also use the provided executables contained in the release version for CLEAPP. Those can be found here:
https://github.com/markmckinnon/cLeapp/releases/tag/v1.0

Using CLEAPP

Run the cleappGUI.py script for the graphical user interface version. It will look like this:

Click around and done

Notice the list of modules on the left. You can parse all or select individual modules. CLEAPP is pretty fast so for most purposes running with all modules enabled is recommended.

Here is a short list of some modules it supports:
  • Chromebook device details
  • Chromebook device logs
  • Chromium Browsers
  • Instagram Threads
  • Chromium LevelDB data stores (Thanks Alex Caithness & Ryan Benson)
  • Microsoft RDP
  • Real VNC
  • Google Docs
  • and tons more...

After CLEAPP finishes processing the output will be in the following formats:
  • HTML report
  • Tab separated values text files for every artifact
  • KML files for artifacts that have geolocation data points
  • SQLite timeline file for artifacts that have timestamps
  • SQlite contacts file for artifacts that have contacts information
The HTML report contains the categories and artifacts on the left of the report.

HTML report

The Device Details tab will have information on the Chromebook like serial number, current operatin system version, and more.

Device Details

One of the interesting facts about Chromebooks is that they can run Android apps. As time permits I plan to merge all ALEAPP artifacts for use in CLEAPP and make sure that both projects support Android artifacts. 

Since this is a community project we will be more than happy to have additional collaborators. 

Get ready for this, Mark has provided Autopsy integration for CLEAPP right out the bat. Check it out here:
https://medium.com/@markmckinnon_80619/cleapp-autopsy-plugin-59ba312beccc


Any questions or any comments I can be reached on twitter @AlexisBrignoni and email 4n6[at]abrignoni[dot]com.

-Brigs