HTTPfy

Port 8733 (ibus)

IANA assigns port 8733 to ibus: iBus.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
ibus TCP iBus Silvano Maffeis -
ibus UDP iBus Silvano Maffeis -

Check what is listening on port 8733

Linux: is anything listening on TCP 8733?
sudo ss -tlnp 'sport = :8733'
Linux: UDP 8733
sudo ss -ulnp 'sport = :8733'
Linux / macOS: which process owns the port
sudo lsof -nP -i :8733
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':8733 '
Windows (Command Prompt)
netstat -ano | findstr :8733
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 8733 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 8733
From Windows
Test-NetConnection HOST -Port 8733
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 8733

Block port 8733 in the firewall

ufw
sudo ufw deny 8733/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 8733 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 8733 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 8733' -Direction Inbound -Protocol TCP -LocalPort 8733 -Action Block
ufw
sudo ufw deny 8733/udp
iptables
sudo iptables -A INPUT -p udp --dport 8733 -j DROP
nftables
sudo nft add rule inet filter input udp dport 8733 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 8733' -Direction Inbound -Protocol UDP -LocalPort 8733 -Action Block

Related ports

8711nvc8732dtp-net8750dey-keyneg8763mc-appserver

All port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.