There are two differing ip addresses with the same mac address ff-ff-ff-ff-ff-ff. Could someone that knows my wifi password do this? I factory reset the router but this is still appearing. What can I do to protect my network?

  • Are you seeing ff-ff-ff-ff-ff-ff as a destination address in a MAC frame? If so, this is normal behavior for a broadcast frame. See practicalnetworking.net/series/arp/traditional-arp.
    – mti2935
    Nov 22 at 21:46
  • 4
    I’m voting to close this question because it is based on misunderstanding network protocols and is not actually about information security. Nov 22 at 22:17
  • I am not sure if it is a destination or not. Typed in 'arp -a' in command and it showed two different ip addresses with ff-ff-ff-ff-ff-ff. The first one seems associated to my router and ends in 255, the other one is from Nov 22 at 22:29
  • Those are two different forms of broadcast address used in IPv4, and it is completely correct for both to use the same link-level broadcast mechanism. See wikipedia. This is not related to security in any way. Nov 23 at 0:18

Don't worry because FF-FF-FF-FF-FF-FF is a broadcast address that used for transmission of service packets. Any device might generate packets with such destination address.

See also: https://en.wikipedia.org/wiki/Broadcast_address

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  • Thanks. Is it possible someone could install something on my computer that can snoop on my traffic? Nov 24 at 20:55

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