Port 3113CS-Authenticate Server

Port assigned for the CS-Authenticate server service from Cliff Diamond and Andy Georgiou.

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

also known as cs-auth-svr

Technical Details

what runs on :3113

CS-Authenticate Server is registered on port :3113 over tcp and udp to Cliff Diamond][Andy Georgiou. 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 :3113

this machine

# linux
sudo ss -tulpn 'sport = :3113'

# macos / bsd
sudo lsof -nP -i :3113

# windows (then: tasklist /FI "PID eq <pid>")
netstat -ano | findstr :3113

another host

nmap -sV -p T:3113 <host>
sudo nmap -sU -sV -p U:3113 <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 :3113

risk score

1/ 10safe

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

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

tcp · udp

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

security overview

no security notes recorded for :3113 yet

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

Record

iana registry entry

port: :3113
service: CS-Authenticate Server
transport: TCPUDP
encryption: cleartext
assignment: iana registered
risk: 1/10safe
category: uncategorised
usage: TCP and UDP port 3113 is assigned to the CS-Authenticate Server service. The registration is held by Cliff Diamond and Andy Georgiou; public deployment details are not recorded.
lookups: 0rank 993
added: 2026-09-04
updated: 2026-09-04
references: IANA service name registry — port 3113

Something wrong?

This record is maintained by the engineers who use port 3113. 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 2026-09-04.

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

browse categories →

ports registered around :3113, by lookups.

port	service	proto	category	risk	views
:3128	Tatsoft Default HTTP Proxy	TCP	Web Services	caution	46.8k
:3128	Squid Proxy HTTP	TCP	Web Services	caution	45.8k
:3100	Tatsoft HTTP Port	TCP	Web Services	caution	19.4k
:3074	Xbox Live / Games for Windows	TCPUDP	Gaming	caution	10.9k
:3050	Interbase/Firebird gds_db	TCPUDP	Databases	caution	10.7k
:3051	Galaxy Server	TCPUDP	Web Services	caution	10.2k
:3101	BlackBerry BES Cloud Comm	TCP	Cloud	caution	7.1k
:3052	APC 3052	TCPUDP	System	safe	0

risk mix of the 8 listed

safe13%
caution88%

0 of 8 encrypted

Port :3113CS-Authenticate Server

Technical Details

Security Information

Related Ports

Port 3113CS-Authenticate Server