Flowise: Cross-workspace credential IDOR in openai-assistants-vector-store

Summary

These endpoints accept a client-controlled credential parameter. The server loads credentials by id and uses them directly, without checking whether that credential belongs to the caller’s workspace. If an attacker knows another workspace’s credentialId, they can use that workspace’s OpenAI key.

Details

Route permissions (assistants:*) only check feature access. They do not check credential ownership. The controller passes req.query.credential straight to the service. The service does findOneBy({ id: credentialId }), decrypts the credential, and calls OpenAI APIs. There is no workspaceId check in this flow, so this is an IDOR.

Impact

• Cross-workspace unauthorized use of stored OpenAI keys.
• Unauthorized read/modify/delete of victim vector stores and files.
• Direct billing impact on victim OpenAI account.
• Multi-tenant boundary violation with practical exploitability.

Reproduction steps

1. Set up two workspaces: A (attacker) and B (victim), each with an OpenAI credential.
2. Log in as a user in workspace A (with assistants-related permissions).
3. Call /api/v1/openai-assistants-vector-store and set credential to B’s credential ID.
4. Example: GET /api/v1/openai-assistants-vector-store?credential=<B_credentialId>.
5. If responses/actions are executed using B’s credential context, the issue is confirmed.