Just want to share my experience, I've this problem for a week and I had used the Malwarewbytes and Kaspersky to scan my computer, no virus or malware could be found.
But when I bypass my router(running TomatoVPN), ie. direct connect my computer to the ISP, no JS:Banker-IC alert appears from Avast. However, once I connect back the router, the alert comes back.
Cheers.