Kafka UI is an Open-Source Web UI for Apache Kafka Management. Kafka UI API allows users to connect to different Kafka brokers by specifying their network address and port. As a separate feature, it also provides the ability to monitor the performance of Kafka brokers by connecting to their JMX ports. JMX is based on the RMI protocol, so it is inherently susceptible to deserialization attacks. A potential attacker can exploit this feature by connecting Kafka UI backend to its own malicious broker. This vulnerability affects the deployments where one of the following occurs: 1. dynamic.config.enabled property is set in settings. It's not enabled by default, but it's suggested to be enabled in many tutorials for Kafka UI, including its own README.md. OR 2. an attacker has access to the Kafka cluster that is being connected to Kafka UI. In this scenario the attacker can exploit this vulnerability to expand their access and execute code on Kafka UI as well. Instead of setting up a legiti…