A security issue exists within 1769 CompactLogix controllers due to the missing validation of sequence numbers and source IP addresses in the CIP protocol. This allows attacker to abuse the exposed Connection ID’s visible on the web interface to perform denial-of-service attacks, resulting in a minor fault.
The product does not validate or incorrectly validates the integrity check values or “checksums” of a message. This may prevent it from detecting if the data has been modified or corrupted in transmission.