{
  "port": 63331,
  "protocol": "tcp",
  "service": "Unassigned (dynamic range)",
  "oneLiner": "No registration, no named service, and more UDP sightings than TCP in Nmap's data.",
  "whatItIs": "63331 falls in the range RFC 6335 reserves for dynamic and private use, so IANA has nothing on it. Nmap's nmap-services carries TCP at 0.000380 and UDP at 0.001004, both \"unknown\", which is why the port appears in a default scan. SANS ISC has an empty service field; the only attribution there is an unsourced visitor comment naming a long-discontinued Microsoft product, which is not verifiable and is not repeated here. What is verifiable is that it is unregistered and unidentified.",
  "exposure": {
    "verdict": "careful",
    "note": "An unidentified listener has unknown authentication and unknown encryption. Keep it internal until you know what it is."
  },
  "checkCommand": "nmap -Pn -sV --version-all -p 63331 TARGET",
  "links": [
    {
      "title": "RFC 6335 — Dynamic Ports (49152-65535)",
      "url": "https://www.rfc-editor.org/rfc/rfc6335.html",
      "kind": "spec"
    },
    {
      "title": "IANA port registry — search 63331",
      "url": "https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=63331",
      "kind": "iana"
    },
    {
      "title": "nmap/nmap — nmap-services frequency data",
      "url": "https://github.com/nmap/nmap/blob/master/nmap-services",
      "kind": "github"
    }
  ]
}