---
id: CVE-2026-33866
aliases:
  - GHSA-46r5-x6jq-v8g6
  - BIT-mlflow-2026-33866
  - PYSEC-2026-94
title: MLflow is vulnerable to an authorization bypass affecting the AJAX endpoint
summary: MLflow is vulnerable to an authorization bypass affecting the AJAX endpoint
severity: medium
cvss: 4.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N'
vendor: mlflow
product: mlflow
ecosystem: pip
affected:
  - mlflow < 3.11.0rc0
patched:
  - mlflow 3.11.0rc0
published: '2026-04-07'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T03:50:42.818312809Z'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-46r5-x6jq-v8g6'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-33866'
  - url: 'https://github.com/mlflow/mlflow/pull/21708'
  - url: >-
      https://github.com/mlflow/mlflow/commit/005b959cacda05d1423356cfcbd9ebeda8ff96a7
  - url: >-
      https://afine.com/blogs/attacking-mlflow-how-ml-artifacts-become-attack-vectors
  - url: 'https://cert.pl/en/posts/2026/04/CVE-2026-33865'
  - url: 'https://github.com/mlflow/mlflow'
  - url: >-
      https://github.com/pypa/advisory-database/tree/main/vulns/mlflow/PYSEC-2026-94.yaml
tags:
  - osv
  - pip
epss: 0.00374
epssPercentile: 0.28606
ingestedAt: '2026-09-12T03:13:01.650Z'
---

## Overview

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

- `mlflow < 3.11.0rc0`

## Remediation

Upgrade to a patched release:

- `mlflow 3.11.0rc0`