Missing files after reboot

[seppaleinen]

Hello!

From what I've seen there's a few posts like this one, but the ones that I could find were about files not on the share folder.
I can't really find any logs or anything out of the ordinary, so I have no idea how much has been lost.
But I had to restart my nas due to a network issue, and when I started it up again, I noticed that some movies that I was watching, wasn't there anymore.

I'm a bit creeped out now, that I don't know why this has happened. If there's been a breach, or if there's some issue that's causing my backups to just silently disappear?

I don't really have many apps running, as I've mostly been using it for storage.

But apps that have been running are
* Download Station
* myQNAPCloud SSL Certificate
* Malware Remover
* Cloudlink
* Python 2.7

AFP/SMB/NFS is enabled
Upnp disabled
no port forwards
two authentication for login


Model: TS-459
Version: 4.2.9