CVE-2021-21687

jenkins: FilePath#untar does not check permission to create symbolic links when unarchiving a symbolic link

Published 4 Nov 2021Modified 17 Jun 2026CWE 862

In the Trivy database since at least 24 Oct 2026, 07:11 UTCWhen it arrived before that build is not recorded.

Severity by source

NVD9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

GHSA9.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Red Hat9.0CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

Bitnami9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Trivy's own label is CRITICAL. Rated critical by NVD, GHSA, Bitnami. Rated lower by Red Hat (high).

Description

Jenkins 2.318 and earlier, LTS 2.303.2 and earlier does not check agent-to-controller access to create symbolic links when unarchiving a symbolic link in FilePath#untar.

Affected packages and fixed versions

Source	Package	Fixed in
bitnami::Bitnami Vulnerability Database	jenkins	2.319.0
maven::GitHub Security Advisory Maven	org.jenkins-ci.main:jenkins-core	2.303.3, 2.319

References

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Vulnerability data compiled from the Trivy vulnerability database (trivy-db, Aqua Security, Apache License 2.0), which aggregates third-party advisories. CVE records are published by The MITRE Corporation under the CVE Terms of Use; CVE is a trademark of MITRE. This product uses data from the NVD API but is not endorsed or certified by the NVD. Severity, titles and advisory data from the GitHub Advisory Database (CC BY 4.0), Red Hat security data (CC BY 4.0) and the other sources linked on each entry. Entries may be summarised or re-formatted; the linked original is the authoritative record.