Kibana versions prior to 5.6.1 had a cross-site scripting (XSS) vulnerability in Timelion that could allow an attacker to obtain sensitive information from or perform destructive actions on behalf of other Kibana users.
An error was found in the X-Pack Security 5.3.0 to 5.5.2 privilege enforcement. If a user has either 'delete' or 'index' permissions on an index in a cluster, they may be able to issue both delete and index requests against that index.
An error was found in the permission model used by X-Pack Alerting 5.0.0 to 5.6.0 whereby users mapped to certain built-in roles could create a watch that results in that user gaining elevated privileges.