Telnet
Legacy remote terminal
Security: Credentials in plaintext; replace with SSH
TCP · Encrypted: No
Port
Port 23
Conventionally used by Telnet. Port assignments are conventions, so confirm the actual listener before you write a rule around this number.
TCPEncrypted: No
Protocols on this port
Where this port appears in the documentation
Exposure guidance
Decide reachability from the identity of the caller, not from the port number. If the service on this port carries credentials or administrative control, restrict it to an administrative network, require strong authentication, and log every session that reaches it.
Nearby ports
In the knowledge graph
Open the interactive map centred on this entity to see everything it connects to and travel outwards from there.