# WHATPORT(6711)

## NAME

port 6711 — Unassigned — Unassigned at IANA; a port that lives mostly in old intrusion-detection signature lists.

Protocol: TCP  
IANA registry

## DESCRIPTION

IANA lists 6707-6713 as Unassigned, and nmap's service database records no name for 6711. It has no registered protocol and no current product default. Its reputation comes from late-1990s Windows backdoor lore, where ports just above 6700 appear in old firewall and IDS rule sets, but there is no authoritative registration or vendor documentation to point at — so treat any listener here as unidentified software rather than as a confirmed anything.

## EXPOSURE

**Expose with care.** Nothing legitimate is expected here. An open 6711 on a Windows host is worth running down to a named process.

## CHECK

```sh
sudo lsof -nP -iTCP:6711 -sTCP:LISTEN
```

## SEE ALSO

- iana — [IANA Service Name and Transport Protocol Port Number Registry — 6711](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=6711) (iana.org)
- source — [nmap-services (Nmap's port/service frequency database)](https://github.com/nmap/nmap/blob/master/nmap-services) (github.com)

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HTML: <https://whatport.net/6711/> · JSON: <https://whatport.net/6711.json> · full dataset: <https://whatport.net/ports.json>