A Polymorphic Typing issue was discovered in FasterXML jackson-databind 2.0.0 through 2.9.10. When Default Typing is enabled (either globally or for a specific property) for an externally exposed JSON endpoint and the service has the apache-log4j-extra (version 1.2.x) jar in the classpath, and an attacker can provide a JNDI service to access, it is possible to make the service execute a malicious payload.