The POST /workflows/{workflowId}/test-runs/new endpoint authorized access using workflow:read rather than workflow:execute. An authenticated user with read-only access to a workflow could trigger a real evaluation test run, causing the workflow to execute via the internal workflow runner. This could result in unintended outbound API calls, data mutations, or other side effects in downstream systems connected to the workflow.

This issue primarily affects instances where the Evaluations feature is in use and where users may have workflow:read access without workflow:execute access, such as deployments using RBAC project roles.

The issue has been fixed in n8n versions 1.123.55, 2.25.7, and 2.26.2. Users should upgrade to one of these versions or later to remediate the vulnerability.

If upgrading is not immediately possible, administrators should consider the following temporary mitigations:

These workarounds do not fully remediate the risk and should only be used as short-term mitigation measures.