Windows Operating System Blocked

What would be the reasoning behind this log? All settings set according to Chiron’s guide. Thanks.

[attachment deleted by admin]

May I please get a mods feed back on this. Thanks.

May I please get an expert answer on this. Thanks.

That depends on the entries you left out of the image.

If both Source and Destination IP are equal then this is the blocking of a Gratuitous ARP packet send by the IP shown in the logging.
Everyday OS’es all send out this type of packets to detect if the IP address received from e.g. DHCP server is in use or not.

This options was available in v5 to enable/disable separately under block ARP stuff.
It seems in v6 this sub-option was lost, and we have already requested it’s return, so that you can chose to block ARP spoofing and if you like Gratuitous ARP separately.

The reason CIS logs this as WOS (Windows Operating System) is because ARP traffic is handled at that point, and does not belong to an application like e.g. Firefox.exe

Thank you Ronny for your very professional answer.

i have wos blocked for udp protocol. any explanation?? thanks.

[attachment deleted by admin]