{
  "port": 6669,
  "protocol": "tcp",
  "service": "IRC (alternate)",
  "oneLiner": "The top of IANA's 6665-6669 IRC range — a plaintext alternate to 6667.",
  "whatItIs": "6669 is the last port in the ircu block IANA assigned for IRC, and servers that listen across the range include it so clients have a fifth fallback. The protocol is identical to 6667: CRLF-terminated text commands, numeric replies, no encryption. Nothing else of note is registered here, so an open 6669 is an IRC daemon or an application squatting on a free port.",
  "exposure": {
    "verdict": "careful",
    "note": "Plaintext like the rest of the range. Offer 6697 with TLS alongside it if the server is public."
  },
  "checkCommand": "printf 'QUIT\\r\\n' | nc -v TARGET 6669",
  "links": [
    {
      "title": "RFC 1459 — Internet Relay Chat Protocol",
      "url": "https://www.rfc-editor.org/rfc/rfc1459.html",
      "kind": "spec"
    },
    {
      "title": "IANA Service Name and Transport Protocol Port Number Registry — 6665-6669 (ircu)",
      "url": "https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=6669",
      "kind": "iana"
    }
  ]
}