# WHATPORT(50003)

## NAME

port 50003 — Unassigned (dynamic range) — No IANA assignment, no known service — typically the third port in a hand-allocated 50000 block.

Protocol: TCP  
IANA registry

## DESCRIPTION

50003 is in the range RFC 6335 sets aside for dynamic and private use, so no registration exists and none is possible. Nmap's service database records it as unknown with a very low open-port frequency. When it does turn up it is almost always because an operator or a container compose file allocated 50000, 50001, 50002, 50003 as a contiguous block for their own services.

## EXPOSURE

**Expose with care.** Meaningless in isolation. Scan the surrounding block, identify each listener, then apply the verdict that the actual service deserves.

## CHECK

```sh
nmap -Pn -sV -p 50000-50010 TARGET
```

## SEE ALSO

- spec — [RFC 6335 — IANA Procedures for Service Name and Transport Protocol Port Number Registry](https://www.rfc-editor.org/rfc/rfc6335.html) (rfc-editor.org)
- iana — [IANA Service Name and Transport Protocol Port Number Registry](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml) (iana.org)

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HTML: <https://whatport.net/50003/> · JSON: <https://whatport.net/50003.json> · full dataset: <https://whatport.net/ports.json>