TCP 9600
Synopsis
- TCP port 9600 is widely used by Omron PLCs for the FINS protocol (Factory Interface Network Service) over Ethernet.
- Real-world devices include Omron CJ-series (CJ1M/CJ2M), CS1, and CP1L/CP1H controllers, many of which listen on TCP/9600 for FINS communications.
- Omron software such as CX-Programmer/CX-Server (and FINS Gateway) uses TCP/9600 to upload/download programs and monitor memory on those PLCs.
- Third-party SCADA/driver software also uses this port for Omron FINS, e.g., Kepware KEPServerEX’s “Omron FINS Ethernet” driver and Inductive Automation Ignition’s “Omron FINS TCP” driver connect by default on TCP/9600.
- In the field, integrators often access remote Omron PLCs via TCP/9600 for data logging, HMI tags, and control.
- Security note: FINS commonly lacks authentication; exposed TCP/9600 services on Omron PLCs have been abused in the wild to read/write PLC memory and start/stop CPUs, so this port is a frequent target in ICS scans and should be firewalled or VPN-only.
Observed activity
Last 30 days
Detailed chart