Description
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).
Remediation
References
http://www.openwall.com/lists/oss-security/2019/09/25/3
https://jenkins.io/security/advisory/2019-09-25/#SECURITY-1498
Related Vulnerabilities
CVE-2019-10375 Vulnerability in maven package hudson.plugins.filesystem_scm:filesystem_scm
CVE-2020-14061 Vulnerability in maven package com.fasterxml.jackson.core:jackson-databind
CVE-2019-10301 Vulnerability in maven package org.jenkins-ci.plugins:gitlab-plugin