Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-04-21 12:08

Modified

2026-04-21 12:33

Summary

Authorization Bypass in MLflow AJAX Endpoint

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

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "mlflow",
        "purl": "pkg:bitnami/mlflow"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.11.1"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "type": "CVSS_V4"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33866"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:lfprojects:mlflow:*:*:*:*:*:*:*:*"
    ],
    "severity": "Medium"
  },
  "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": "BIT-mlflow-2026-33866",
  "modified": "2026-04-21T12:33:30.555Z",
  "published": "2026-04-21T12:08:47.512Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://afine.com/blogs/attacking-mlflow-how-ml-artifacts-become-attack-vectors"
    },
    {
      "type": "WEB",
      "url": "https://cert.pl/en/posts/2026/04/CVE-2026-33865/"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mlflow/mlflow/pull/21708"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33866"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Authorization Bypass in MLflow AJAX Endpoint"
}

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

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

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

Credits

Sławomir Zakrzewski (AFINE)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-33866",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-14T15:12:33.985809Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-14T15:12:44.168Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://github.com/",
          "defaultStatus": "unaffected",
          "packageName": "mlflow",
          "product": "Mlflow",
          "repo": "https://github.com/mlflow/",
          "vendor": "Mlflow",
          "versions": [
            {
              "lessThanOrEqual": "3.10.1",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "S\u0142awomir Zakrzewski (AFINE)"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
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              "base64": false,
              "type": "text/html",
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            }
          ],
          "value": "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"
        }
      ],
      "impacts": [
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          "capecId": "CAPEC-115",
          "descriptions": [
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              "lang": "en",
              "value": "CAPEC-115: Authentication Bypass"
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      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "LOW",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
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            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
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            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
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          "scenarios": [
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      "providerMetadata": {
        "dateUpdated": "2026-04-09T13:30:36.155Z",
        "orgId": "4bb8329e-dd38-46c1-aafb-9bf32bcb93c6",
        "shortName": "CERT-PL"
      },
      "references": [
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          "tags": [
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          ],
          "url": "https://github.com/mlflow/mlflow/pull/21708"
        },
        {
          "tags": [
            "third-party-advisory"
          ],
          "url": "https://cert.pl/en/posts/2026/04/CVE-2026-33865/"
        },
        {
          "tags": [
            "exploit",
            "technical-description"
          ],
          "url": "https://afine.com/blogs/attacking-mlflow-how-ml-artifacts-become-attack-vectors"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Authorization Bypass in MLflow AJAX Endpoint",
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    "datePublished": "2026-04-07T12:57:44.380Z",
    "dateReserved": "2026-03-24T13:13:32.905Z",
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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

Vulnerability from bitnami_vulndb

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

Tags

Sightings

Nomenclature