# WHATPORT(22)

## NAME

port 22 — SSH — SSH — encrypted remote login, remote command execution, and the transport under scp/sftp and git-over-ssh.

Protocol: TCP  
IANA registry

## DESCRIPTION

sshd listens on 22, exchanges a version banner, then runs a key exchange that authenticates the server by host key and the user by public key, password, or keyboard-interactive. On top of that transport ride interactive shells, port forwards, sftp, and `git@host` clones. It is on essentially every Linux and BSD host and on macOS when Remote Login is enabled. On a public IP it gets continuous automated password-guessing traffic, which is noise, not a breach.

## EXPOSURE

**Fine to expose.** Safe to expose with public-key auth only and PasswordAuthentication disabled; the risk is weak passwords, not the port.

## CHECK

```sh
nc -v github.com 22
```

## SEE ALSO

- spec — [RFC 4253 — The Secure Shell (SSH) Transport Layer Protocol](https://www.rfc-editor.org/rfc/rfc4253.html) (rfc-editor.org)
- docs — [OpenSSH (official project site)](https://www.openssh.org/) (openssh.org)
- source — [Portable OpenSSH source repository](https://github.com/openssh/openssh-portable) (github.com)
- 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/22/> · JSON: <https://whatport.net/22.json> · full dataset: <https://whatport.net/ports.json>