CVE-2021-21686: Jenkins

High severity, CVSS 8.1. EPSS: 2% chance of exploitation in the next 30 days.

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.

Affected products

• Jenkins Jenkins: before 2.303.3 (fixed in 2.303.3); before 2.319 (fixed in 2.319)

Published 2021-11-04. Last modified 2026-06-17.