MQTT client can receive retained messages on a topic not allowed by SimpleAuthenticationPlugin ACL configurationA client (clientA) publish a message, with retain flag set to true, to a topic that is allowed to publish to by the SimpleAuthenticationPlugin.
Then if a client (clientB) that isn't allowed to subscribe this topic, tries to subscribe this topic, the SimpleAuthenticationPlugin throws a security exception but the client (clientB) receives the retained message published by clientA.*NOTE*: This is not reproducible on A-MQ 6.2.