The API token-issuing service in Jenkins before 1.606 and LTS before 1.596.2 allows remote attackers to gain privileges via a "forced API token change" involving anonymous users.
https://blog.carnal0wnage.com/2019/02/jenkins-security-180cve-2015-1814-poc.html
https://wiki.jenkins-ci.org/display/SECURITY/Jenkins+Security+Advisory+2015-03-23
https://bugzilla.redhat.com/show_bug.cgi?id=1205616