Port 3104Autocue Time Service

UDP port 3104 is assigned to the Autocue Time Service.

transport
udp

single transport

in transit
cleartext

payload readable on path

assignment
official

registered with iana

risk
1/10

safe

lookups
0

rank 993 of 4,028 · top 25%

Technical Details

what runs on :3104

Autocue Time Service is registered on port :3104 over udp to Geoff Back. 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 found open rarely. What's listening is often not the registered service, so check before you assume.

find what's listening on :3104

this machine
# linux
sudo ss -ulpn 'sport = :3104'

# macos / bsd
sudo lsof -nP -i :3104

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :3104
another host
sudo nmap -sU -sV -p U:3104 <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 :3104

risk score

1/ 10safe

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

system averages 2.6 across 904 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 :3104 yet

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

the 8 most looked-up other ports in system — 904 ports carry that label.

risk mix of the 8 listed

  • caution100%

0 of 8 encrypted