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Vulnerability record · CVE-2021-21691 · published 4 November 2021

CVE-2021-21691: Jenkins link following vulnerability

Jenkins · Jenkins

Creating symbolic links is possible without the 'symlink' agent-to-controller access control permission in Jenkins 2.318 and earlier, LTS 2.303.2 and earlier.

9.8 CVSS 3.1 Critical EPSS 2.1% · top 19.0% CWE-59 · Link following
9.8CVSS 3.1 base score, v2 7.5
2.1%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

Creating symbolic links is possible without the 'symlink' agent-to-controller access control permission in Jenkins 2.318 and earlier, LTS 2.303.2 and earlier.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://www.jenkins.io/security/advisory/2021-11-04/#SECURITY-2455 Vendor Advisory
https://www.jenkins.io/security/advisory/2021-11-04/#SECURITY-2455 Vendor Advisory

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-21691), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.