Frequent QNAP Crashes with FTP published to the Internet

[amdaxiom]

I published FTP on my QNAP to the Internet and created a user with no admin rights just for FTP. The files I need are not secure and publicly available, mainly utilities that I require every now and then. Nothing I am concerned about. In any case I still setup lockout policies as I don't want people hacking into my system.

I noticed recently my QNAP being down continuously and restarting by itself. I'd hear a beep as it was booting back up. After several times of it doing this I got a little concerned and on the next time the system was up I took a look at the logs. I was getting IP lockouts due to failed logins every few seconds from multiple IP addresses. For some reason I was being targeted by a botnet or something. I was suspcious that the thousands of login tries were causing the QNAP to reboot - maybe some process was taking up memory or too many requests were causing an issue?

In any case I did close the port as the QNAP was pretty much unusable with the constant restarts. As soon as I closed my FTP port the reboots stopped (and of course the IP lockouts stopped as well).

So if you happen to publish services and all of a sudden have your QNAP restarting maybe you are under attack by a botnet and the QNAP resources are being consumed.

As an FYI I do have 16GB of RAM in mine as I used to run some VM's on the box before. It is the 5 bay QNAP with the AMD quad core processor, I forget the exact model.