Stack uses broadcast IP address as destination for List-Identity response

In case the stack receives two List-Identity request from another subnet and no gateway address is configured or the gateway is not reachable, the stack sends the ListIdentity response with the broadcast address as destination IP address.
See Specification Volume 2 Edition 1.16 Chapter "2-4.2 ListIdentity":

A connection originator may use the ListIdentity command to locate and identify potential
targets. This command shall be sent as a unicast message using TCP or UDP, or as a broadcast
message using UDP and does not require that a session be established. The reply shall always be sent as a unicast message.
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This can lead to a very high CPU load in case that there are other netX EtherNet/IP devices in the network that have the same misbehavior. In that case those broadcast frames are bouncing between those node and will not be taken out of the network (see capture file ListIdentity_BroadCast_Response_MessageBouncing.pcap).