A privilege escalation flaw was found in Tomcat when the JMX Remote Lifecycle Listener was enabled. A local attacker without access to the Tomcat process or configuration files could be able to manipulate the RMI registry to perform a man-in-the-middle attack. The attacker could then capture user names and passwords used to access the JMX interface and gain complete control over the Tomcat instance. When using FORM authentication with Apache Tomcat 9.0.0.M1 to 9.0.29, 8.5.0 to 8.5.49 and 7.0.0 to 7.0.98 there was a narrow window where an attacker could perform a session fixation attack. The window was considered too narrow for an exploit to be practical but, erring on the side of caution, this issue has been treated as a security vulnerability. A flaw was found in Apache Tomcat, where the payload length in a WebSocket frame was not correctly validated. Invalid payload lengths could trigger an infinite loop. Multiple requests with invalid payload lengths could lead to a denial of service. The highest threat from this vulnerability is to system availability