{"id":"CVE-2026-33866","aliases":["BIT-mlflow-2026-33866","EUVD-2026-19609","GHSA-46r5-x6jq-v8g6","PYSEC-2026-94"],"status":"published","title":"Authorization Bypass in MLflow AJAX Endpoint","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.\n\n \nThis issue affects MLflow version through 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Tracking","Patch","fix","web"]},{"url":"https://cert.pl/en/posts/2026/04/CVE-2026-33865/","tags":["third-party-advisory","Third Party Advisory","advisory"]},{"url":"https://afine.com/blogs/attacking-mlflow-how-ml-artifacts-become-attack-vectors","tags":["exploit","technical-description","Exploit","Third Party Advisory","advisory","evidence","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33866","tags":["web","advisory"]},{"url":"https://cert.pl/en/posts/2026/04/CVE-2026-33865","tags":["web"]},{"url":"https://github.com/mlflow/mlflow/commit/005b959cacda05d1423356cfcbd9ebeda8ff96a7","tags":["web"]},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/mlflow/PYSEC-2026-94.yaml","tags":["web"]},{"url":"https://github.com/advisories/GHSA-46r5-x6jq-v8g6","tags":["advisory"]},{"url":"https://github.com/","tags":["web"]},{"url":"https://github.com/mlflow/","tags":["web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33866.json","tags":["advisory"]},{"url":"https://github.com/mlflow/mlflow","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2026-33866","title":"Authorization Bypass in MLflow AJAX Endpoint","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.\n\n \nThis issue affects MLflow version through 3.10.1","status":"published","published":"2026-04-07T12:57:44.38Z","modified":"2026-04-14T15:12:44.168Z","cvss":[{"version":"4.0","score":5.3,"vector":"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","level":"medium","assessor":"cna"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T14:20:08.009733Z"}],"euvd":[{"id":"EUVD-2026-19609","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.\n\n \nThis issue affects MLflow version through 3.10.1","status":"published","published":"2026-04-07T12:57:44Z","modified":"2026-04-14T15:12:44Z","cvss":[{"version":"4.0","score":5.3,"vector":"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","level":"medium"}],"updated_at":"2026-11-02T19:24:25.999353Z"}],"ghsa":[{"id":"GHSA-46r5-x6jq-v8g6","title":"MLflow is vulnerable to an authorization bypass affecting the AJAX endpoint","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.\n\n \nThis issue affects MLflow version through 3.10.1","status":"published","published":"2026-04-07T15:30:50Z","modified":"2026-06-06T00:57:59Z","cvss":[{"version":"4.0","score":5.3,"vector":"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","level":"medium"},{"version":"3.1","score":4.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-862"],"updated_at":"2026-11-02T14:40:18.682012Z"}],"nvd":[{"id":"CVE-2026-33866","description":"MLflow is vulnerable to an authorization bypass affecting the AJAX endpoint used to download saved model artifacts. 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