Actuator, a Spring Boot feature, allows system introspection and monitoring, letting developers easily check and analyze application metrics. In Eureka client versions before 1.8.7, XStream was used for serialization and deserialization. Its default settings permitted arbitrary code execution, enabling attackers to craft malicious serialized data for code execution.This rule supports to defend the A6: Vulnerable and Outdated Components of OWASP Top 10 - 2021. Other reference:None