Malicious website I haven't visited repeatedly blocked

[RPeachey19 0]

I'm getting a notification that a website I haven't ever heard of or visitied is being blocked repeatedly (260 messages and counting in the past 10 minutes or so). The ESET antivirus software is notifying me of this, but it gives me the feeling I've been hacked or there's something fishy going on. Any suggestions for what I can do to stop this website from trying to access my computer? 

Here's the notification I'm getting:

[Marcos 5,468]

It was a false positive, fixed several hours ago.