When an affected product receives a valid CIP message from an unauthorized or unintended source to Port 2222/TCP, Port 2222/UDP, Port 44818/TCP, or Port 44818/UDP that instructs the CPU to stop logic execution and enter a fault state, a DoS can occur. This situation could cause loss of availability and a disruption of communication with other connected devices. Rockwell Automation EtherNet/IP products; 1756-ENBT, 1756-EWEB, 1768-ENBT, and 1768-EWEB communication modules; CompactLogix L32E and L35E controllers; 1788-ENBT FLEXLogix adapter; 1794-AENTR FLEX I/O EtherNet/IP adapter; ControlLogix 18 and earlier; CompactLogix 18 and earlier; GuardLogix 18 and earlier; SoftLogix 18 and earlier; CompactLogix controllers 19 and earlier; SoftLogix controllers 19 and earlier; ControlLogix controllers 20 and earlier; GuardLogix controllers 20 and earlier; and MicroLogix 1100 and 1400
https://www.cisa.gov/news-events/ics-advisories/icsa-13-011-03
https://rockwellautomation.custhelp.com/app/answers/detail/aid/470156
https://rockwellautomation.custhelp.com/app/answers/detail/aid/470155
https://rockwellautomation.custhelp.com/app/answers/detail/a_id/470154
http://www.us-cert.gov/control_systems/pdf/ICSA-13-011-03.pdf
http://rockwellautomation.custhelp.com/app/answers/detail/a_id/54102