CVE-2021-21611

Description

Jenkins 2.274 and earlier, LTS 2.263.1 and earlier does not escape display names and IDs of item types shown on the New Item page. This results in a stored cross-site scripting (XSS) vulnerability exploitable by attackers able to specify display names or IDs of item types. As of the publication of this advisory, the Jenkins security team is not aware of any plugins published via the Jenkins project update center that allow doing this. Jenkins 2.275, LTS 2.263.2 escapes display names and IDs of item types shown on the New Item page.

How to fix CVE-2021-21611

To remediate CVE-2021-21611, upgrade the affected package to a fixed version below.

• —upgrade to 2.274.1 or later
• —upgrade to 2.263.2 or later

Is CVE-2021-21611 being exploited?

Low — EPSS is 0.3%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 2.274.1
• from 0, < 2.263.2

CVSS scores

References (4)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2021-21611
• PATCHgithub.com/jenkinsci/jenkins
• WEBgithub.com/jenkinsci/jenkins/commit/8c451b08886561a914ef0c30cbb9d40ea33a9bbe
• WEBwww.jenkins.io/security/advisory/2021-01-13/#SECURITY-2171