Executive brief
Jenkins Script Security Plugin provides a sandbox that lets administrators safely run user-supplied scripts and Pipelines without exposing the Jenkins server to malicious code. This vulnerability allows attackers with script authoring permissions to bypass the sandbox and execute arbitrary code with full Jenkins controller privileges by exploiting how the plugin handles methods added dynamically to classes at runtime, compromising the security of the entire Jenkins instance.
Technical details
The vulnerability is a sandbox bypass in Jenkins Script Security Plugin 1415.v9a_f9b_3a_c253d and earlier. The plugin fails to intercept and validate calls to methods that are added dynamically to a class at runtime within sandboxed Groovy scripts. An attacker with permission to define and execute sandboxed scripts or Pipelines can leverage this gap to invoke unvetted dynamically-added methods that perform sensitive operations, bypassing the intended sandbox restrictions. The attack requires script authoring privileges on the Jenkins instance. The issue is resolved in version 1422.v06869826dd9b_ and later, which adds proper validation of dynamically-added method calls.
Affected products
- Jenkins Script Security Plugin 1415.v9a_f9b_3a_c253d and earlier
Timeline
- 2026-09-16: disclosed
- 2026-09-16: other: CVSS score and CVE ID published