Executive brief
Kestra is an automation platform used to orchestrate complex data workflows and business processes. A security flaw allows any logged-in user to view the output files of tasks belonging to other users or teams within the same organization. This could lead to the exposure of sensitive information such as database passwords, API keys, or private customer data handled by the platform.
Technical details
An Insecure Direct Object Reference (IDOR) exists in the 'previewFileFromExecution' endpoint (GET /api/v1/{tenant}/executions/{executionId}/file/preview). The vulnerability is caused by 'ExecutionController.java' failing to validate the return value of the 'validateFile' method, which is intended to enforce execution-level and namespace-level isolation. While sibling methods correctly handle redirects when a user requests a file URI belonging to a different execution, the preview endpoint ignores this check and proceeds to fetch the file from storage. An attacker with low-privileged access can provide a 'kestra://' URI belonging to a victim's execution to retrieve sensitive output data. The issue is fixed in versions 1.0.45 and 1.3.21.
Affected products
- kestra-io Kestra < 1.0.45, >= 1.1.0 < 1.3.21
Timeline
- 2026-06-03: advisory: GitHub Security Advisory published by vendor
- 2026-06-26: disclosed: CVE published to NVD