In the last two months we have noticed increased number of complaints from cloud drive users loosing their data due to Cryptolocker attacks. A closer research lead us to couple of IT and security forums discussing cloud drive data backup procedures for few major players in the market.
For example if the files are stored in the Google Drive and you have deleted them by mistake, you have an option to pull them back from the Trash folder, but if the Trash folder has been emptied you have only 25 days to get help from your Google Apps administrator. There is no way for a non-admin user to restore data on their own. Additionally such restore is all-or-nothing activity. This is not a regular backup restore process, where you can view and select which files will be restored before the process is started. With Google Drive restore process you will have no idea, what will actually be restored. It is easy to imagine how such process could result in all kinds of other files being restored that you did not intend to get back.
So is this process good enough to make sure that your data is recoverable? Not at all, just imagine what would happen, if your computer was hit with the Cryptolocker virus? All files in the Google Drive file path on your local computer would be renamed and encrypted and then the locked files would re-synced back to the Google Drive in the cloud, using the native app function in the background.
Now, as your files have not been deleted, they are not in the Trash folder so there is no simple way to restore your files back to the original state. The only way forward would be to delete the current file version and resort back to the original file within the Google Admin console. It could be an option for few files, but what if you lost all your files and photos? This process would not work for thousands of files unless you know what "Drive API" and were able to code an application, that was able to retrieve revision feed of the affected files, grab the data inside of those files and replace them with a new unencrypted version in the same location.
In short make sure to backup your cloud drive the same way you backup your regular data or use provider that has fully available data backup and restore functionality within their offering.