My Cloud NAS - Protect on network

I run Norton 360 on my Windows 10 PC: 

I have a Western Digital My Cloud 3TB NAS attached to the computer via USB, and attached to my network wirelessly. On a daily basis, I receive a notification from my ISP (Xfinity) of an IP Reputation threat to my NAS device. I check my firmware version, reboot the device and scan it for malware. The IP address being attacked is inside my home network. I have been told that a NAS can be the weakest security link on a home network.

The purpose of this device is to access it when I am not home. Therefore, I am seeking guidance on how to protect the device, while maintaining access to it using the client application on my smartphone. Is this a problem requiring a firewall solution? Please advise. Thank you.

 

 

Hello again. Just a follow-up to see how things worked out and if we can assist further.

SA

Hello. Is the alert being generated via an e-mail or text message, maybe being sent directly to your PC or mobile device? FWIW!! Xfinity forums discusses your specific issue here. They don't even bother with an answer other than its the router alerting you that an IP address with a known signature fitting detection criteria has been detected. This xfinity article MAY be of some help for you as well. 

SA