A man in the middle vulnerability exists in Jenkins Ansible Plugin 0.8 and older in AbstractAnsibleInvocation.java, AnsibleAdHocCommandBuilder.java, AnsibleAdHocCommandInvocationTest.java, AnsibleContext.java, AnsibleJobDslExtension.java, AnsiblePlaybookBuilder.java, AnsiblePlaybookStep.java that disables host key verification by default.