Jenkins Script Security sandbox protection could be circumvented during the script compilation phase by applying AST transforming annotations such as @Grab
to source code elements.
Both the pipeline validation REST APIs and actual script/pipeline execution are affected.
This allowed users with Overall/Read permission, or able to control Jenkinsfile or sandboxed Pipeline shared library contents in SCM, to bypass the sandbox protection and execute arbitrary code on the Jenkins controller.
All known unsafe AST transformations in Groovy are now prohibited in sandboxed scripts.
packetstormsecurity.com/files/152132/Jenkins-ACL-Bypass-Metaprogramming-Remote-Code-Execution.html
www.rapid7.com/db/modules/exploit/multi/http/jenkins_metaprogramming
access.redhat.com/errata/RHBA-2019:0326
access.redhat.com/errata/RHBA-2019:0327
github.com/jenkinsci/pipeline-model-definition-plugin/commit/083abd96e68fd89f556a0cd53db5f878dbf09b92
jenkins.io/security/advisory/2019-01-08/#SECURITY-1266
nvd.nist.gov/vuln/detail/CVE-2019-1003002
www.exploit-db.com/exploits/46572