n8n: Crafted Workflow ID Gives Access to Data Tables in Other Projects

Impact

n8n accepted a client-supplied ID when a workflow was created and cached the owner project of each workflow in memory by its ID. A specially chosen ID made the cache return an invalid owner project, and the Data Table project check built from it then matched every project. A member who can create and run workflows can list, read, change and delete Data Table rows in all projects of the instance.

Patches

The issue has been fixed in n8n versions 2.44.1 and 2.43.5. Users should upgrade to one of these versions or later to remediate the vulnerability.

Workarounds

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

• Restrict n8n instance access to fully trusted users only.
• Audit existing workflows for any whose stored ID is __proto__ and remove them.
• Disable the Data Tables module if it is not required.

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