Port 4000Terabase

TCP/UDP 4000 is assigned to Terabase and has a documented historical conflict with ICQ messaging.

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

also known as ICQ

1 other service is registered on port 4000. compare all 2 →

Technical Details

what runs on :4000

The IANA assignment covers both TCP and UDP, but no widely documented Terabase protocol behavior or handshake is established. The registry notes that ICQ also used port 4000; this is a historical alternative use, not a reliable way to identify a current listener. ICQ's service was discontinued in 2024, and its commonly documented client port was 5190.

Security Information

exposure of :4000

risk score

1/ 10safe

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

voice and chat averages 3.4 across 174 ports — this one sits 2.4 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

tcp · udp

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

security overview

There is no established Terabase security profile to assess, and an open port should be identified by inspecting the actual listener rather than assuming it is Terabase or ICQ. ICQ is a discontinued legacy service; avoid exposing an unidentified or obsolete service to the internet.

Record

iana registry entry

port: :4000
service: Terabase
transport: TCPUDP
encryption: cleartext
assignment: iana registered
risk: 1/10safe
category: Voice and Chat
usage: IANA assigns this port to Terabase, registered to Thor Olson. The registry also notes historical ICQ use; that does not mean an open port today is necessarily an ICQ service.
lookups: 0rank 993
added: 2026-10-02
updated: 2026-10-02
references: IANA service name registry — port 4000

Something wrong?

This record is maintained by the engineers who use port 4000. 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 2026-10-02.

01edit any field on a page of its own
02a model checks it for accuracy and spam
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edit this record →back to the registry

Related Ports

all 174 in voice and chat →

the 8 most looked-up other ports in voice and chat — 174 ports carry that label.

port	service	proto	category	risk	views
:9090	Openfire Admin Console	TCP	Web Services	caution	34.2k
:1513	Garena Gaming	TCPUDP	Gaming	caution	33.1k
:9091	Openfire Admin Console (SSL)	TCPtls	Web Services	caution	28.3k
:2031	Mobrien Chat	TCPUDP	Web Services	caution	27.7k
:1720	H.323 Signaling	TCP	Network Services	caution	26.5k
:6005	Camfrog Chat	TCP	Voice and Chat	caution	25.2k
:3001	Miralix Phone Monitor	TCP	Network Services	caution	21.7k
:9009	Pichat Server	TCPUDP	Network Services	caution	19.7k

risk mix of the 8 listed

caution100%

1 of 8 encrypted

Port :4000Terabase

Technical Details

Security Information

Related Ports

Port 4000Terabase