This advisory announces multiple vulnerabilities in Jenkins, CloudBees Jenkins Platform and CloudBees Jenkins Solutions.
Stored XSS vulnerability in tool names exploitable by administrators
Jenkins administrators can configure tools, such as JDK, Maven, or Ant, that will be available in job configurations for use by build scripts. Some tool names are not properly escaped on job configuration forms, resulting in a stored cross-site scripting vulnerability.
Tools confirmed to be affected are:
JDK (provided by Jenkins core)
Ant (provided by Ant plugin)
Others may also be affected by this.
Please be aware that this vulnerability can only be exploited by Jenkins administrators, as they’re the only ones able to define tools. In regular Jenkins configurations, administrators are able to run any code and install any plugin. Therefore this vulnerability only really affects installations that don’t grant administrators the Run Scripts, Configure Update Sites, and/or Install Plugins permissions.