It was discovered that the RMI (Java Remote Method Invocation) server implementation in the JMX (Java Management Extensions) component of OpenJDK did not restrict which classes can be deserialized when deserializing authentication credentials. A remote unauthenticated attacker able to connect to a JMX port could possibly use this flaw trigger deserialization flaws.

A flaw was found in the RMI registry implementation in the RMI component of OpenJDK. Incorrect handling of the server-side dispatch could lead to selection of an incorrect skeleton class.

The default configuration in Apache Cassandra 1.2.0 through 1.2.19, 2.0.0 through 2.0.13, and 2.1.0 through 2.1.3 binds an unauthenticated JMX/RMI interface to all network interfaces, which allows remote attackers to execute arbitrary Java code via an RMI request.

Apache Cassandra versions 2.1.0 to 2.1.22, 2.2.0 to 2.2.19, 3.0.0 to 3.0.23, and 3.11.0 to 3.11.9, when using 'dc' or 'rack' internodeencryption setting, allows both encrypted and unencrypted internode connections. A misconfigured node or a malicious user can use the unencrypted connection despite not being in the same rack or dc, and bypass mutual TLS requirement.