Port 44818 (EtherNet/IP (CIP))

EtherNet/IP explicit messaging for Rockwell/Allen-Bradley PLCs; implicit I/O uses UDP 2222.

Registered (user) port, 1024-49151 TCPUDP Industrial control (ICS/SCADA) Do not expose to the internet

What port 44818 is used for

EtherNet/IP explicit messaging for Rockwell/Allen-Bradley PLCs; implicit I/O uses UDP 2222.

Security: should port 44818 be open?

Do not expose to the internet. No authentication in the base protocol; isolate OT networks.

IANA assignment

Service nameProtoDescriptionAssigneeReference

EtherNet-IP-2 TCP EtherNet/IP messaging IANA assigned this well-formed service name as a replacement for "EtherNet/IP-2".
New contact added for port 44818 on 2008-02-01 Brian Batke 2 -

EtherNet/IP-2 TCP EtherNet/IP messaging
New contact added for port 44818 on 2008-02-01 This entry is an alias to "EtherNet-IP-2". This entry is now historic, not usable for use with many common service discovery mechanisms. Brian Batke 2 -

EtherNet-IP-2 UDP EtherNet/IP messaging IANA assigned this well-formed service name as a replacement for "EtherNet/IP-2".
New contact added for port 44818 on 2008-02-01 Brian Batke 2 -

EtherNet/IP-2 UDP EtherNet/IP messaging
New contact added for port 44818 on 2008-02-01 This entry is an alias to "EtherNet-IP-2". This entry is now historic, not usable for use with many common service discovery mechanisms. Brian Batke 2 -

Check what is listening on port 44818

Linux: is anything listening on TCP 44818?

sudo ss -tlnp 'sport = :44818'

Linux: UDP 44818

sudo ss -ulnp 'sport = :44818'

Linux / macOS: which process owns the port

sudo lsof -nP -i :44818

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':44818 '

Windows (Command Prompt)

netstat -ano | findstr :44818

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 44818 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine

nc -vz -w 5 HOST 44818

From Windows

Test-NetConnection HOST -Port 44818

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

nc -vzu -w 5 HOST 44818

Block port 44818 in the firewall

ufw

sudo ufw deny 44818/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 44818 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 44818 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 44818' -Direction Inbound -Protocol TCP -LocalPort 44818 -Action Block

ufw

sudo ufw deny 44818/udp