Vulnerability-Lookup

PYSEC-2026-94

Vulnerability from pysec - Published: 2026-04-07 13:16 - Updated: 2026-05-20 09:19

Details

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

Severity

4.3 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Impacted products

Name	purl
mlflow	pkg:pypi/mlflow

Aliases

CVE-2026-33866

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "mlflow",
        "purl": "pkg:pypi/mlflow"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.11.0rc0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.0.1",
        "0.1.0",
        "0.2.0",
        "0.2.1",
        "0.3.0",
        "0.4.0",
        "0.4.1",
        "0.4.2",
        "0.5.0",
        "0.5.1",
        "0.5.2",
        "0.6.0",
        "0.7.0",
        "0.8.0",
        "0.8.1",
        "0.8.2",
        "0.9.0",
        "0.9.0.1",
        "0.9.1",
        "1.0.0",
        "1.1.0",
        "1.1.1.dev0",
        "1.10.0",
        "1.11.0",
        "1.12.0",
        "1.12.1",
        "1.13",
        "1.13.1",
        "1.14.0",
        "1.14.1",
        "1.15.0",
        "1.16.0",
        "1.17.0",
        "1.18.0",
        "1.19.0",
        "1.2.0",
        "1.20.0",
        "1.20.1",
        "1.20.2",
        "1.21.0",
        "1.22.0",
        "1.23.0",
        "1.23.1",
        "1.24.0",
        "1.25.0",
        "1.25.1",
        "1.26.0",
        "1.26.1",
        "1.27.0",
        "1.28.0",
        "1.29.0",
        "1.3.0",
        "1.30.0",
        "1.30.1",
        "1.4.0",
        "1.5.0",
        "1.6.0",
        "1.7.0",
        "1.7.1",
        "1.7.2",
        "1.8.0",
        "1.9.0",
        "1.9.1",
        "2.0.0",
        "2.0.0rc0",
        "2.0.1",
        "2.1.0",
        "2.1.1",
        "2.10.0",
        "2.10.1",
        "2.10.2",
        "2.11.0",
        "2.11.1",
        "2.11.2",
        "2.11.3",
        "2.11.4",
        "2.12.0",
        "2.12.1",
        "2.12.2",
        "2.13.0",
        "2.13.1",
        "2.13.2",
        "2.14.0",
        "2.14.0rc0",
        "2.14.1",
        "2.14.2",
        "2.14.2.dev0",
        "2.14.3",
        "2.15.0",
        "2.15.0rc0",
        "2.15.1",
        "2.16.0",
        "2.16.1",
        "2.16.2",
        "2.17.0",
        "2.17.0rc0",
        "2.17.1",
        "2.17.2",
        "2.18.0",
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        "2.19.0",
        "2.19.0rc0",
        "2.2.0",
        "2.2.1",
        "2.2.2",
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        "2.20.1",
        "2.20.2",
        "2.20.3",
        "2.20.4",
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        "2.21.0rc0",
        "2.21.1",
        "2.21.2",
        "2.21.3",
        "2.22.0",
        "2.22.0rc0",
        "2.22.1",
        "2.22.2",
        "2.22.3",
        "2.22.4",
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        "2.3.0",
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        "2.3.2",
        "2.4.0",
        "2.4.1",
        "2.4.2",
        "2.5.0",
        "2.6.0",
        "2.7.0",
        "2.7.1",
        "2.8.0",
        "2.8.1",
        "2.9.0",
        "2.9.1",
        "2.9.2",
        "3.0.0",
        "3.0.0rc0",
        "3.0.0rc1",
        "3.0.0rc2",
        "3.0.0rc3",
        "3.0.1",
        "3.1.0",
        "3.1.0rc0",
        "3.1.1",
        "3.1.2",
        "3.1.3",
        "3.1.4",
        "3.10.0",
        "3.10.0rc0",
        "3.10.1",
        "3.2.0",
        "3.2.0rc0",
        "3.3.0",
        "3.3.0rc0",
        "3.3.1",
        "3.3.2",
        "3.4.0",
        "3.4.0rc0",
        "3.5.0",
        "3.5.0rc0",
        "3.5.1",
        "3.6.0",
        "3.6.0rc0",
        "3.7.0",
        "3.7.0rc0",
        "3.8.0",
        "3.8.0rc0",
        "3.8.1",
        "3.9.0",
        "3.9.0rc0"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33866"
  ],
  "details": "MLflow is vulnerable to an authorization bypass affecting the AJAX endpoint used to download saved model artifacts. Due to missing access\u2011control validation, a user without permissions to a given experiment can directly query this endpoint and retrieve model artifacts they are not authorized to access.\n\n \nThis issue affects MLflow version through 3.10.1",
  "id": "PYSEC-2026-94",
  "modified": "2026-05-20T09:19:08.285844Z",
  "published": "2026-04-07T13:16:47Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://cert.pl/en/posts/2026/04/CVE-2026-33865/"
    },
    {
      "type": "FIX",
      "url": "https://github.com/mlflow/mlflow/pull/21708"
    },
    {
      "type": "EVIDENCE",
      "url": "https://afine.com/blogs/attacking-mlflow-how-ml-artifacts-become-attack-vectors"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-33866 (GCVE-0-2026-33866)

Vulnerability from cvelistv5 – Published: 2026-04-07 12:57 – Updated: 2026-04-14 15:12

Title

Authorization Bypass in MLflow AJAX Endpoint

Summary

Severity

5.3 (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

CWE

CWE-862 - Missing Authorization

Assigner

CERT-PL

References

3 references

URL	Tags
https://github.com/mlflow/mlflow/pull/21708	patch
https://cert.pl/en/posts/2026/04/CVE-2026-33865/	third-party-advisory
https://afine.com/blogs/attacking-mlflow-how-ml-a…	exploittechnical-description

Impacted products

1 product

Vendor	Product	Version
Mlflow	Mlflow	Affected: 0 , ≤ 3.10.1 (semver)

Credits

Sławomir Zakrzewski (AFINE)

Show details on NVD website

JSON

To clipboard

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                "role": "CISA Coordinator",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

PYSEC-2026-94

CVE-2026-33866 (GCVE-0-2026-33866)

Tags

Sightings

Nomenclature