Port 1027IPv6 Behind NAT44 CPEs

Reserved UDP service for IPv6 connectivity behind NAT44 customer-premises equipment.

transport: udp
in transit: cleartext
assignment: official
risk: 1/10
lookups: 0

also known as 6a44

Technical Details

what runs on :1027

IPv6 Behind NAT44 CPEs is registered on port :1027 over udp to IESG, assigned August 2012. We don't have a technical write-up for it beyond the IANA registry entry.

In nmap's internet-wide scan data this port is never observed open, so if it's open on your network it's more likely a custom or misconfigured service than the registered one.

find what's listening on :1027

this machine

# linux
sudo ss -ulpn 'sport = :1027'

# macos / bsd
sudo lsof -nP -i :1027

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :1027

another host

sudo nmap -sU -sV -p U:1027 <host>

run it? the handshake, the implementations you meet in the wild and the flags that matter come from the engineers who do.

add technical details

Security Information

exposure of :1027

risk score

1/ 10safe

routine exposure. this port is rarely the way in on its own — keep it patched and logged and move on.

network services averages 2.6 across 1,618 ports — this one sits 1.6 below.

in transit

cleartext

credentials and payloads are readable by anyone on path

assignment

official

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

reachable over

udp

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

security overview

no security notes recorded for :1027 yet

known exploits, hardening advice, what a compromise looks like — suggest an edit if you know its exposure.

Record

iana registry entry

port: :1027
service: IPv6 Behind NAT44 CPEs
transport: UDP
encryption: cleartext
assignment: iana registered
risk: 1/10safe
category: Network Services
usage: UDP port 1027 is assigned to the IESG for IPv6 Behind NAT44 CPEs. The registry provides no further product, protocol, or deployment details, and the service has not been observed open in internet-wide nmap scans.
lookups: 0rank 993
added: 2026-09-16
updated: 2026-09-16
references: IANA service name registry — port 1027
RFC 6751

Something wrong?

This record is maintained by the engineers who use port 1027. 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 2026-09-16.

01edit any field on a page of its own
02a model checks it for accuracy and spam
03clean and confident goes live immediately

edit this record →back to the registry

Related Ports

all 1,618 in network services →

the 8 most looked-up other ports in network services — 1,618 ports carry that label.

port	service	proto	category	risk	views
:9080	Groove RPC	TCPUDP	Web Services	caution	70.8k
:6543	Jetnet	UDP	Network Services	caution	65.3k
:5938	TeamViewer	TCPUDP	Remote Access	caution	65.0k
:8291	Winbox MikroTik Admin	TCP	Security	caution	62.9k
:3233	WhiskerControl Protocol	TCPUDP	Network Services	caution	61.9k
:3268	Microsoft Global Catalog (GC)	TCPUDP	Security	caution	54.6k
:135	Microsoft EPMAP	TCPUDP	Security	caution	51.9k
:3128	Tatsoft Default HTTP Proxy	TCP	Web Services	caution	46.8k

risk mix of the 8 listed

caution100%

0 of 8 encrypted

Port :1027IPv6 Behind NAT44 CPEs

Technical Details

Security Information

Related Ports

Port 1027IPv6 Behind NAT44 CPEs