You mention onedrive, funny (perhaps not) story: I've seen 5~ situations at different organisations where malware in the form of cryptolocker spreads through onedrive destroying everyone's files and connected computers more often than not, also interestingly I've seen onedrive completely mess up its versioning system and rid the organisation at hands files dated and resulting in days if not weeks of re-work. I can't believe these things seem to go unreported as if I've seen it (at least) 5 times others must have witnessed it many more, onedrive seems like one the carrier of bad all that is bad and vulnerable in the Microsoft ecosystem. Note: I am not some anti-corp / anti-ms fanboy, I'm simply stating what I've witnessed which I have not with other platforms.