A safe connection to the Internet
Turn the power switch off.
We don't know all details and history of this latest vulnerability but the chances are that it's a result of a feature being updated. Companies that build devices that connect to the Internet, normally invest effort in making them secure, but then features are added and independently updated - resulting is this type of problem.
The solution? If Google was making these devices then the NAS operating system would be updated every six months, and the NAS web server, DLNA server and other NAS apps would be updated few days like my Android phone updates. - I think that this guarantees Internet security, the bugs aren't fixed - they are just moved every few days to
prevent hacking make it difficult to reliably hack the device.