Unregistered and unnamed in scanner databases; open on well under a tenth of a percent of hosts.
33899 has no IANA assignment and no service name in Nmap's database, which records it open on about 0.04% of scanned hosts. Like everything between 32768 and 60999 it doubles as a Linux ephemeral port, so an open socket here is as likely to be an outbound connection as a service. Identify it by the process, not by the number.
Expose with care
Nothing about the port number tells you whether it is safe; run a version scan or check the owning process before allowing it through a firewall.
$ nc -vz -w 3 TARGET 33899Seen this on your network? Beige Box scans your Wi-Fi and shows every open port on every device — and its Ports tool links straight back here.
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Corrections or a missing port? Reply @rimrocksystems.