HTTPfy

Port 777 (multiling-http)

IANA assigns port 777 to multiling-http: Multiling HTTP.

Well-known (system) port, 0-1023 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
multiling-http TCP Multiling HTTP Alejandro Bonet -
multiling-http UDP Multiling HTTP Alejandro Bonet -

Check what is listening on port 777

Linux: is anything listening on TCP 777?
sudo ss -tlnp 'sport = :777'
Linux: UDP 777
sudo ss -ulnp 'sport = :777'
Linux / macOS: which process owns the port
sudo lsof -nP -i :777
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':777 '
Windows (Command Prompt)
netstat -ano | findstr :777
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 777 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 777
From Windows
Test-NetConnection HOST -Port 777
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 777

Block port 777 in the firewall

ufw
sudo ufw deny 777/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 777 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 777 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 777' -Direction Inbound -Protocol TCP -LocalPort 777 -Action Block
ufw
sudo ufw deny 777/udp
iptables
sudo iptables -A INPUT -p udp --dport 777 -j DROP
nftables
sudo nft add rule inet filter input udp dport 777 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 777' -Direction Inbound -Protocol UDP -LocalPort 777 -Action Block

Related ports

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