Application Analysis Continued
On the Application Analysis team, we have been busy recovering data from deleted programs. Please refer to this link for our previous blog post and more information about what we do!
Since our last update, the team has been busy digging through Google Drive. While we found a lot of information, we also learned about some unknown features of the application. When a user starts the installation for Google Drive, the application creates a new folder. Also added is a syncing program to download and upload the files locally. This is important to be aware of because once one deletes a program, this local folder and all the files within are still available. This is a good feature for user interface, even if it is at the cost of security. If the user has files on their drive and still need them offline, it provides easy access. The problem arises if the user wanted all traces of their google drive gone from their computer in a single deletion.
In our experiment, we created test profiles and tested all of the capabilities of the application. Then, we investigated what information we could access after deleting the application from the computer. The separate folder had all of the information that was linked and downloaded to Google Drive and its local folder. The problem with drive storage versus cloud storage is that anything that you have downloaded lacks the need for a user login and password. In addition, the folder created during installation is shown under “Quick Access” even after deletion, making it easily visible to unwanted users.
When the team started investigating the evidence in Magnet Axiom (a commercial digital forensics investigation tool), the beneficial applications of this method became apparent. The deletion of the application doesn’t retain the Google user’s information (password, email, name, etc), but the URL to the Google document is.
All of the files that were stored under the “Google Drive” folder locally were accessible from Axiom. In addition, all files contained a link back to the drive that can be opened in browser. When you go to open the file online links from Axiom to the Google Drive, unless you possess the login information, the rest of the information is safe. In a way this ensures future data security, as any future iterations of files are not accessible after the deletion of the app unless the user is accessing it. It is a bit of both worlds for accessibility and security, as expected from such a large and well-developed company.
The team has also spent time sifting through Dropbox data from a similarly structured experiment. After we loaded the virtual machine file into Axiom, we saw that the system stores all Dropbox-based files, even after deleting the program from the computer.
Axiom processes a variety of information: when the user logged into the program, when they downloaded the default Dropbox files, the files/folders Dropbox stores and creates, when they were created, and the direct file paths of the files.
The system Google implemented is still very much present in Dropbox. The program created a folder in the file system locally that remained after the deletion of the application. However, the information in the image above does not include a link back to Dropbox. If there was not a folder for the information, there would be very little distinguishing information within the files showing that Dropbox downloaded them. Dropbox however unlike Google, does not have its own format(Google Documents, Google Presentation, etc) or online application for documents and files, a factor which likely influenced this approach.
Considering the type of user interaction these services provide, this outcome is surprising, but not entirely difficult to understand. It is important information to anyone who may be trying to compromise your data. In order to rid your system of all the above information, the user will need to do it manually. It is clear to see that one can’t delete all of the information by uninstalling the desktop version of the program.
In the coming weeks we will be investigating Steam. As the largest video game platform worldwide, it would need to keep its users’ data safe.
We will be sure to let everyone know the verdict on our next Application Analysis blog!
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