{
  "port": 5910,
  "protocol": "tcp",
  "service": "ats-atn (ICAO) / VNC display :10 in practice",
  "oneLiner": "Registered for air traffic services over the ATN; in the wild it is VNC display :10.",
  "whatItIs": "IANA registers 5910 as ats-atn, \"Air Traffic Services applications using ATN\", over TCP and UDP, with a separate SCTP registration named cm (Context Management). These are aeronautical telecommunication network services on private infrastructure. On a normal host, 5910 is 5900 plus display 10 — a hypervisor that has allocated ten guest consoles, or a machine with a long-lived set of VNC sessions.",
  "exposure": {
    "verdict": "never",
    "note": "A double-digit VNC display usually means a virtualization host handing out guest consoles. That is an administrative surface and should be reachable only from the management network."
  },
  "checkCommand": "nc -w 3 TARGET 5910 | head -c 12; echo",
  "links": [
    {
      "title": "IANA port registry — 5910 (ats-atn / cm)",
      "url": "https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=5910",
      "kind": "iana"
    },
    {
      "title": "RFC 6143 — The Remote Framebuffer Protocol",
      "url": "https://datatracker.ietf.org/doc/html/rfc6143",
      "kind": "spec"
    }
  ]
}