A denial-of-service vulnerability exists in the Rockwell Automation affected products when specially crafted packets are sent to the CIP Security Object. If exploited the device will become unavailable and require a factory reset to recover.
Rockwell Automation was made aware of a vulnerability that causes all affected controllers on the same network to result in a major nonrecoverable fault(MNRF/Assert). This vulnerability could be exploited by sending abnormal packets to the mDNS port. If exploited, the availability of the device would be compromised.