CVE-2026-33760 Langflow: IDOR/BOLA in Monitor API — Missing Ownership Enforcement on 7 Endpoints
Authenticated users can read, modify, or delete other users' data in Langflow due to missing ownership checks on monitor API endpoints.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33760?
CVE-2026-33760 is a high-severity missing authorization vulnerability in Langflow Langflow, published on 23 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.0, Langflow's /api/v1/monitor router exposes 7 endpoints that perform read, write, and delete operations on user-owned resources — messages, sessions, build artifacts, and LLM transaction logs — without verifying that the authenticated requester owns the targeted resource. Any authenticated user can read, modify, rename, or permanently delete another user's data by supplying the target's resource ID or flow_id. This is a classic IDOR/BOLA vulnerability. Notably, the same source file (monitor.py) contains one correctly-implemented endpoint that uses an ownership check, demonstrating the correct pattern was known but inconsistently applied. This vulnerability is fixed in 1.9.0.
Weakness: CWE-639
Which versions are affected by CVE-2026-33760?
3 open source packages ship an affected version, including langflow. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
langflow PyPI | All versions | 1.9.0 |
langflow PyPI | All versions | 1.9.0 |
langflow PyPI | All versions | 1.9.0 |
Products include Langflow Langflow.
How do I fix CVE-2026-33760?
Upgrade langflow to 1.9.0 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-33760 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33760 exists.
Other vulnerabilities in Langflow Langflow
Sources
Also known as GHSA-9c59-2mvc-vfr8, PYSEC-2026-242.