{
  "port": 5850,
  "protocol": "tcp",
  "service": "Unassigned",
  "oneLiner": "No IANA registration and no established service; a round number that ad hoc software likes.",
  "whatItIs": "5850 has no entry in the IANA service registry and no widely deployed default. Round numbers like this get chosen by hand for internal services, staging deployments, and one-off proxies, which is the usual explanation for finding one open. Nothing about the port number itself tells you the protocol, so probe the service or check the process.",
  "exposure": {
    "verdict": "careful",
    "note": "An unidentified listener, most likely something internal that was never designed to face the internet. Confirm before exposing."
  },
  "checkCommand": "sudo lsof -nP -iTCP:5850 -sTCP:LISTEN",
  "links": [
    {
      "title": "IANA port registry — 5850 (unassigned)",
      "url": "https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=5850",
      "kind": "iana"
    }
  ]
}