One observation, and where it came from.
outbound to 198.51.100.74:8443, a destination no host has used before
This observation is part of a written scenario. It did not come off a real network, and nothing on this deployment did.
{
"kind": "security",
"detection_type": "rare_destination",
"principal": "ws-0148->198.51.100.74:8443",
"source_address": null,
"asset": null,
"confidence": 0.9
}