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.
Due to a memory leak, a denial-of-service vulnerability exists in the Rockwell Automation affected products. A malicious actor could exploit this vulnerability by performing multiple actions on certain web pages of the product causing the affected products to become fully unavailable and require a power cycle to recover.
CVE 2021-22681 https://www.rockwellautomation.com/en-us/trust-center/security-advisories/advisory.PN1550.html and send a specially crafted CIP message to the device. If exploited, a threat actor could help prevent access to the legitimate user and end connections to connected devices including the workstation. To recover the controllers, a download is required which ends any process that the controller is running.