Port 8008 (HTTP alternate (8008))

Alternate HTTP port used by Chromecast/Google Cast devices, Matrix Synapse's default listener and some appliances.

Registered (user) port, 1024-49151 TCP Web Expose only to trusted sources

What port 8008 is used for

Alternate HTTP port used by Chromecast/Google Cast devices, Matrix Synapse's default listener and some appliances.

Expose only to trusted sources. Usually a LAN-side or backend service; not meant for direct internet access.

Service nameProtoDescriptionAssigneeReference

http-alt TCP HTTP Alternate James Gettys -

http-alt UDP HTTP Alternate James Gettys -

Linux: is anything listening on TCP 8008?

sudo ss -tlnp 'sport = :8008'

Linux / macOS: which process owns the port

sudo lsof -nP -i :8008

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':8008 '

Windows (Command Prompt)

netstat -ano | findstr :8008

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 8008 -State Listen | Select LocalAddress,OwningProcess

From another machine

nc -vz -w 5 HOST 8008

From Windows

Test-NetConnection HOST -Port 8008

Replace 203.0.113.10 with the address or network you trust. With ufw, make sure the default incoming policy is deny.

ufw (one trusted source)

sudo ufw allow from 203.0.113.10 to any port 8008 proto tcp

iptables

sudo iptables -A INPUT -p tcp --dport 8008 -s 203.0.113.10 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 8008 -j DROP

nftables

sudo nft add rule inet filter input ip saddr 203.0.113.10 tcp dport 8008 accept
sudo nft add rule inet filter input tcp dport 8008 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'TCP 8008 trusted' -Direction Inbound -Protocol TCP -LocalPort 8008 -RemoteAddress 203.0.113.10 -Action Allow

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Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.