RabbitMQ is a messaging and streaming broker. Prior to 4.2.5, the RabbitMQ management UI renders the x-internal-purpose queue or exchange argument into an HTML title attribute without proper escaping on the Queues and Exchanges pages, allowing a user with permission to declare a queue or exchange to execute JavaScript in another user's browser. This issue is fixed in version 4.2.5.

RabbitMQ is a messaging and streaming broker. Prior to 4.2.6, RabbitMQ AMQP 0-9-1 allows an existing consumer to keep receiving messages after OAuth token expiry or connection.updatesecret refresh to reduced scopes because existing consumers are not canceled or reauthorized at delivery time after the channel user state changes. This issue is fixed in version 4.2.6.

RabbitMQ is a messaging and streaming broker. From 4.2.0 to before 4.2.4, RabbitMQ's MQTT plugin allows for topic-level authorization using regular expressions with variable substitution. Administrators can create patterns such as ^{clientid}-sensors$ to restrict user access to topics that include their client ID. However, the clientid is provided by the user in the MQTT CONNECT packet and is inserted into the regex pattern without escaping special regex characters. This flaw enables an authenticated MQTT user to inject regex operators to bypass authorization. This vulnerability is fixed in 4.2.4 and 4.3.0.