433
NNSP
Low RiskTCP — Messaging
Port Overview
Port Number
433
Service Name
NNSP
Transport Protocol
TCP
Category
Messaging
Security Risk
Low
Port Range
Well-Known (0-1023)
What is Port 433?
Port 433 is assigned to NNSP (Network News Transfer Protocol Security), used for secure NNTP transfers. Rarely used as Usenet has declined.
TCP
Messaging
Security Considerations
Port 433 (NNSP) is classified as low risk. This service uses encryption or has a minimal attack surface, making it relatively safe to expose.
Recommendation: Standard security practices apply. Keep software updated and monitor access.