Authorization Bypass in MLflow AJAX Endpoint_CVE-2026-33866

5.3 / 10

MEDIUM

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

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

Basic Information

ID CVE-2026-33866

Source CERT-PL

Published Apr 7, 2026 at 12:57

Modified Apr 9, 2026 at 13:30

Affected Product

Vendor Mlflow

Product Mlflow

Affected Versions Mlflow Mlflow 0

CWE Classification

CWE-862

References

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    "published": "2026-04-07T12:57:44.380Z",
    "modified": "2026-04-09T13:30:36.155Z",
    "type": "cve",
    "title": "Authorization Bypass in MLflow AJAX Endpoint",
    "source": "CERT-PL",
    "references": "https://github.com/mlflow/mlflow/pull/21708\nhttps://cert.pl/en/posts/2026/04/CVE-2026-33865/\nhttps://afine.com/blogs/attacking-mlflow-how-ml-artifacts-become-attack-vectors",
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