CVE-2021-21686: Improper Link Resolution Before File Access ('Link Following')

November 4, 2021 (updated November 22, 2023)

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

References

nvd.nist.gov/vuln/detail/CVE-2021-21686
www.jenkins.io/security/advisory/2021-11-04/

Detect and mitigate CVE-2021-21686 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Learn more about Dependency Scanning →