Port 43188 (reachout)

IANA assigns port 43188 to reachout: REACHOUT.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference

reachout TCP REACHOUT Roman Kriis -

reachout UDP REACHOUT Roman Kriis -

Linux: is anything listening on TCP 43188?

sudo ss -tlnp 'sport = :43188'

Linux: UDP 43188

sudo ss -ulnp 'sport = :43188'

Linux / macOS: which process owns the port

sudo lsof -nP -i :43188

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':43188 '

Windows (Command Prompt)

netstat -ano | findstr :43188

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 43188 -State Listen | Select LocalAddress,OwningProcess

From another machine

nc -vz -w 5 HOST 43188

From Windows

Test-NetConnection HOST -Port 43188

UDP probe (no reply does not prove it is closed)

nc -vzu -w 5 HOST 43188

ufw

sudo ufw deny 43188/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 43188 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 43188 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 43188' -Direction Inbound -Protocol TCP -LocalPort 43188 -Action Block

ufw

sudo ufw deny 43188/udp

iptables

sudo iptables -A INPUT -p udp --dport 43188 -j DROP

nftables

sudo nft add rule inet filter input udp dport 43188 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block UDP 43188' -Direction Inbound -Protocol UDP -LocalPort 43188 -Action Block

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