CVE-2026-3198 Improper Access Control in mlflow/mlflow
Authenticated users can bypass authorization checks to enumerate sensitive gateway secrets and model definitions in MLflow when basic-auth is enabled.
- 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-2026-3198?
CVE-2026-3198 is a medium-severity missing authorization vulnerability in Lfprojects Mlflow, published on 2 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
MLflow 3.9.0 with basic-auth (`--app-name basic-auth`) fails to enforce authorization checks for multiple Gateway API 'list' endpoints. Specifically, the `BEFORE_REQUEST_HANDLERS` dictionary in `mlflow/server/auth/__init__.py` does not include entries for `ListGatewaySecretInfos`, `ListGatewayEndpoints`, and `ListGatewayModelDefinitions`. This allows any authenticated user, regardless of their assigned permissions, to enumerate all gateway secrets, endpoints, and model definitions. This vulnerability exposes sensitive information, such as API keys, endpoint configurations, and proprietary model definitions, to unauthorized users.
Weakness: CWE-284
Which versions are affected by CVE-2026-3198?
4 open source packages ship an affected version, including mlflow. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mlflow Bitnami | From 3.9.0 | 3.10.0 |
mlflow PyPI | All versions | 3.11.0rc0 |
mlflow PyPI | All versions | 3.11.0rc0 |
mlflow PyPI | All versions | 3.11.0rc0 |
Products include Lfprojects Mlflow.
How do I fix CVE-2026-3198?
Upgrade mlflow to a fixed version for your release line: 3.10.0 or 3.11.0rc0.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-3198 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-3198 exists.
Other vulnerabilities in Lfprojects Mlflow
- CVE-2026-64849 MLflow Server-Side Request Forgery
- CVE-2025-15379 Command Injection in mlflow/mlflow
- CVE-2024-0520 Remote Code Execution due to Full Controlled File Write in mlflow/mlflow
- CVE-2023-6977 Path Traversal: '\..\filename'
- CVE-2023-6709 Improper Neutralization of Special Elements Used in a Template Engine in mlflow/mlflow
Sources
Also known as BIT-mlflow-2026-3198, GHSA-r5m9-wm49-959f, PYSEC-2026-2659.