521
RIPng
High RiskUDP — System & Infrastructure
Port Overview
Port Number
521
Service Name
RIPng
Transport Protocol
UDP
Category
System & Infrastructure
Security Risk
High
Port Range
Well-Known (0-1023)
What is Port 521?
Port 521 is assigned to RIPng, the IPv6 adaptation of RIP defined in RFC 2080. Should be restricted to trusted network segments.
UDP
System & Infrastructure
Security Considerations
Port 521 (RIPng) is classified as high risk. This port is a common target for automated scanning and brute-force attacks. If you must expose it, restrict access to known IP addresses.
Recommendation: Use firewall rules to whitelist trusted IPs. Enable rate limiting and intrusion detection.