Is Microsoft Changing Data on OneDrive?

Posted by ownCloud GmbH – 9. May 2014

We don’t know for sure, we certainly became a bit concerned when we read this piece.

Sean Byrne of Myce writes:

“When OneDrive got stuck in an endless loop of trying to sync a few files and the issue returned when I tried clearing its cache as instructed on Microsoft’s discussion forum, I decided to stop syncing the OneDrive folder and backed it up. I then deleted the original synced folder and got OneDrive to start syncing it again, so it would get a fresh copy from the cloud. In an aim to check if any files got damaged due to the earlier syncing issue, I used a utility called MD5summer to create MD5 hashes for its content and repeated this process for the freshly synced folder. To my surprise, the vast majority of the files showed ‘Checksum did not match’. Surely most of my files haven’t gone corrupt?”

After some investigation, Byrne tracked the corruption to OneDrive. This is incredibly frightening to businesses using OneDrive for sensitive data. We know some other File Sync and Share cloud services, track the data in different ways, to change data is, well, frightening.

According to Byrne:

“So what this means is that people who use OneDrive for Business or SharePoint need to be very careful with what they sync with it, especially those handling third party data due to confidentiality issues. For example, if an employee needs to transfer confidential files that absolutely must not be touched between its laptop and PC and decides to do so through a synced folder in OneDrive for Business, those files will end up being inadvertently modified without the user’s knowledge. This could have severe consequences if let’s say a file is used as evidence in a court case. How do you prove that the company did not intentionally modify it?

“Based on Myce testing, we found that the consumer version of OneDrive (formerly SkyDrive) does not appear to any modify files, whether synced with the desktop product or through the web interface. We also tested BitTorrent Sync and found that it does not modify any files either, even when testing a 1GB folder with a wide range of file types.”

This bares watching, but the only true way to protect sensitive data is not to put it in the public cloud to begin with. Use the storage and data protection tools you already have and give employees an access tool they will actually use.

Please fill out the form below to get your download.


Please deactivate your script blocker or use a different browser to load the form.

By submitting this form, you are granting ownCloud GmbH permission to contact you. You can revoke permission any time using the unsubscribe link found at the bottom of every email or by sending an email to info@owncloud.com