IA Squad
SearchPT
python · langflowCritical

Langflow IDOR Vulnerability in /api/v1/responses Endpoint Fixed in 1.9.1

An IDOR vulnerability in `/api/v1/responses` endpoint allowed authenticated attackers to execute any flow by specifying another user's flow ID.

20 Jun 2026Read 1 minSeverity: act now

What changed

An IDOR vulnerability in `/api/v1/responses` endpoint allowed authenticated attackers to execute any flow by specifying another user's flow ID. Fixed in Langflow 1.9.1 by enforcing user ownership checks in `get_flow_by_id_or_endpoint_name`.

Who it affects

All Langflow instances before 1.9.1; authenticated users could execute arbitrary flows belonging to other users.

What to do today

Upgrade to Langflow 1.9.1 or later immediately.

The trail
Collected Audited Written Published