CVE-2019-10401
In Jenkins 2.196 and earlier, LTS 2.176.3 and earlier, the f:expandableTextBox form control interpreted its content as HTML when expanded, resulting in a stored XSS vulnerability exploitable by users with permission to define its contents (typically Job/Configure).
Versions it affects
Software versions checked with the free lookup that CVE-2019-10401 applies to, and the release that fixes it where the sources name one.
Is this running somewhere in your estate?
The Vulnerability Reporter inventories every machine and tells you when an advisory like this one applies to you.