0
Reserved
Low RiskTCP/UDP — System & Infrastructure
Port Overview
Port Number
0
Service Name
Reserved
Transport Protocol
TCP/UDP
Category
System & Infrastructure
Security Risk
Low
Port Range
Well-Known (0-1023)
What is Port 0?
Port 0 is reserved by IANA and is not used for any service. In programming, specifying port 0 tells the OS to assign an available ephemeral port automatically.
TCP/UDP
System & Infrastructure
Commonly Used
Security Considerations
Port 0 (Reserved) 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.