CVE-2021-21686

Name: CVE-2021-21686
Creator: NVD / NIST
Published: 2021-11-04T17:15:08.277+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.1/10EPSS 1.91%

Last modified Jun 17, 2026

CVE-2021-21686 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. File path filters in the agent-to-controller security subsystem of Jenkins 2.318 and earlier, LTS 2.303.2 and earlier do not canonicalize paths, allowing operations to follow symbolic links to outside allowed directories.. EPSS estimates a 1.91% chance of exploitation in the next 30 days.

Description

File path filters in the agent-to-controller security subsystem of Jenkins 2.318 and earlier, LTS 2.303.2 and earlier do not canonicalize paths, allowing operations to follow symbolic links to outside allowed directories.

Metrics

CVSS 3.1

8.1/10

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

EPSS Probability

1.91%

77.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-59

Affected Software

Vendor	Product	Versions
Jenkins	Jenkins	< 2.303.3
Jenkins	Jenkins	< 2.319

References

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

Timeline

Published: Nov 4, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-21686?

How severe is CVE-2021-21686?

CVE-2021-21686 has a CVSS score of 8.1/10 (HIGH severity). The EPSS model estimates a 1.91% probability of exploitation in the next 30 days.

How do I fix CVE-2021-21686?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-21686?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST