A sandbox bypass vulnerability exists in Jenkins Script Security Plugin 1.53 and earlier in src/main/java/org/jenkinsci/plugins/scriptsecurity/sandbox/groovy/GroovySandbox.java, src/main/java/org/jenkinsci/plugins/scriptsecurity/sandbox/groovy/SecureGroovyScript.java that allows attackers with Overall/Read permission to execute arbitrary code on the Jenkins master JVM.