Jenkins Groovy Plugin sandbox bypass vulnerability

A sandbox bypass vulnerability exists in Jenkins Groovy Plugin 2.0 and earlier in src/main/java/hudson/plugins/groovy/StringScriptSource.java that allows attackers with Overall/Read permission to provide a Groovy script to an HTTP endpoint that can result in arbitrary code execution on the Jenkins master JVM. In version 2.1, the affected HTTP endpoint applies a safe Groovy compiler configuration preventing the use of unsafe AST transforming annotations.