CVE-2021-21682

Description

Jenkins stores jobs and other entities on disk using their name shown on the UI as file and folder names. On Windows, when specifying a file or folder with a trailing dot character (`example.`), the file or folder will be treated as if that character was not present (`example`). As both are legal names for jobs and other entities in Jenkins 2.314 and earlier, LTS 2.303.1 and earlier, this could allow users with the appropriate permissions to change or replace configurations of jobs and other entities. Jenkins 2.315, LTS 2.303.2 does not allow names of jobs and other entities to end with a dot character.

How to fix CVE-2021-21682

To remediate CVE-2021-21682, upgrade the affected package to a fixed version below.

• —upgrade to 2.314.1 or later
• —upgrade to 2.315 or later

Is CVE-2021-21682 being exploited?

Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 2.314.1
• >= 2.304, < 2.315

CVSS scores

References (4)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2021-21682
• WEBgithub.com/jenkinsci/jenkins/commit/c2c2b59071265aea07f88d5e95297c0a433921c3
• WEBwww.jenkins.io/security/advisory/2021-10-06/#SECURITY-2424
• WEBwww.openwall.com/lists/oss-security/2021/10/06/1