HTTPfy

Port 8765 (ultraseek-http)

IANA assigns port 8765 to ultraseek-http: Ultraseek HTTP.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
ultraseek-http TCP Ultraseek HTTP Walter Underwood -
ultraseek-http UDP Ultraseek HTTP Walter Underwood -

Check what is listening on port 8765

Linux: is anything listening on TCP 8765?
sudo ss -tlnp 'sport = :8765'
Linux: UDP 8765
sudo ss -ulnp 'sport = :8765'
Linux / macOS: which process owns the port
sudo lsof -nP -i :8765
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':8765 '
Windows (Command Prompt)
netstat -ano | findstr :8765
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 8765 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 8765
From Windows
Test-NetConnection HOST -Port 8765
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 8765

Block port 8765 in the firewall

ufw
sudo ufw deny 8765/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 8765 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 8765 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 8765' -Direction Inbound -Protocol TCP -LocalPort 8765 -Action Block
ufw
sudo ufw deny 8765/udp
iptables
sudo iptables -A INPUT -p udp --dport 8765 -j DROP
nftables
sudo nft add rule inet filter input udp dport 8765 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 8765' -Direction Inbound -Protocol UDP -LocalPort 8765 -Action Block

Related ports

8763mc-appserver8764openqueue8766amcs8767core-of-source

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