CVE-2026-33866
MEDIUM4.3EPSS 0.01%Authorization Bypass in MLflow AJAX Endpoint
Published: 4/7/2026Modified: 5/20/2026
Description
MLflow is vulnerable to an authorization bypass affecting the AJAX endpoint used to download saved model artifacts. Due to missing access‑control validation, a user without permissions to a given experiment can directly query this endpoint and retrieve model artifacts they are not authorized to access. This issue affects MLflow version through 3.10.1
Affected packages (3)
- Bitnami/mlflowfrom 0, < 3.11.1
- PyPI/mlflowfrom 0, <= 3.10.1
- PyPI/mlflowfrom 0, < 3.11.0rc0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N |
| osv | CVSS 3.1 | MEDIUM4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
References (7)
- ADVISORYhttps://cert.pl/en/posts/2026/04/CVE-2026-33865/
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-33866
- PATCHhttps://github.com/mlflow/mlflow
- WEBhttps://afine.com/blogs/attacking-mlflow-how-ml-artifacts-become-attack-vectors
- WEBhttps://cert.pl/en/posts/2026/04/CVE-2026-33865
- WEBhttps://github.com/mlflow/mlflow/commit/005b959cacda05d1423356cfcbd9ebeda8ff96a7
- WEBhttps://github.com/mlflow/mlflow/pull/21708