SMB:BruteForce attacks identified by unknown MAC address

Hello Buckner,
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Hello,

Three times today AVG has blocked a threat labeled SMB:BruteForce. When I look at the details it gives me a MAC address rather than an IP address for the source of the attack. According to my router, this MAC address isn't part of my network.

I'm worried that since it's brute force it will eventually get an. Any way to further identify or block the source of the attacks?

Thank you for your efforts, Buckner.
We'll check and help you out.
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