Port 4128NuFW

Port for the NuFW decision delegation protocol used to delegate firewall access decisions.

transport: tcp · udp
in transit: encrypted
assignment: official
risk: 4/10
lookups: 0

Technical Details

what runs on :4128

NuFW uses this port for its decision-delegation control protocol: a NuFW firewall component submits connection or packet authorization context and receives the corresponding policy decision from the NuFW authentication service. The protocol is implementation-specific rather than a generic text service; TCP is the normal transport for the persistent component-to-component exchange, while the IANA registration also covers UDP. NuFW deployments commonly protect this inter-component communication with TLS/certificate-based authentication, and the listening port can be changed in configuration.

Security Information

exposure of :4128

risk score

4/ 10caution

worth attention. how exposed you are depends on configuration — don't leave it reachable from the internet without a reason.

security averages 3.1 across 347 ports — this one sits 0.9 above.

in transit

encrypted

payloads are protected on the wire

assignment

official

registered with iana for this service — scanners fingerprint it by number

reachable over

tcp · udp

udp is connectionless — source addresses are trivially spoofed and it is a reflection favourite

security overview

This port should normally be reachable only between trusted NuFW components, not from the public Internet. Exposure could allow probing of the firewall's authorization service and, if authentication or certificate validation is misconfigured, attempts to influence firewall decisions; restrict it with network policy and use NuFW's authenticated encrypted channel.

Record

iana registry entry

port: :4128
service: NuFW
transport: TCPUDP
encryption: tls / encrypted
assignment: iana registered
risk: 4/10caution
category: Security Network Services
usage: Port 4128 is used by NuFW, an authenticated firewall system, for communication between the firewall daemon and its authentication or authorization service. Engineers typically encounter it on NuFW gateways and their associated NuAuth servers rather than as a general-purpose application endpoint.
lookups: 0rank 993
added: 2026-09-05
updated: 2026-09-22
references: IANA service name registry — port 4128

Something wrong?

This record is maintained by the engineers who use port 4128. Every field on it is editable — change what's wrong, say how you know, and a reviewer publishes it, usually within a minute. Last touched 2026-09-22.

01edit any field on a page of its own
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edit this record →back to the registry

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all 347 in security →

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risk mix of the 8 listed

caution100%

2 of 8 encrypted

Port :4128NuFW

Technical Details

Security Information

Related Ports

Port 4128NuFW