---
id: CVE-2026-4035
aliases:
  - GHSA-g35p-px32-whv6
  - BIT-mlflow-2026-4035
title: >-
  MLflow: Environment variable injection in AI Gateway secrets enables
  server-side credential exfiltration
summary: >-
  MLflow: Environment variable injection in AI Gateway secrets enables
  server-side credential exfiltration
severity: critical
cvss: 9.1
cvssVector: 'CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L'
vendor: mlflow
product: mlflow
ecosystem: pip
affected:
  - mlflow < 3.11.0
patched:
  - mlflow 3.11.0
published: '2026-06-03'
updated: '2026-07-10'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-g35p-px32-whv6'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-4035'
  - url: >-
      https://github.com/mlflow/mlflow/commit/4a3f2f720cb4f058c9e0c5b883e0acc9ab64a7f3
  - url: 'https://access.redhat.com/security/cve/CVE-2026-4035'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2484318'
  - url: 'https://github.com/mlflow/mlflow'
  - url: 'https://huntr.com/bounties/f8e591a0-0f19-4910-b82e-16c9956f2233'
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4035.json
tags:
  - osv
  - pip
epss: 0.00521
epssPercentile: 0.43222
ingestedAt: '2026-07-11T18:57:04.420Z'
---

## Overview

A vulnerability in mlflow/mlflow versions prior to 3.11.0 allows for the resolution of environment variables in AI Gateway secrets, which can be exploited to exfiltrate sensitive server-side environment credentials to an attacker-controlled endpoint. This issue arises because the `api_key` field in gateway secrets can accept `$ENV_VAR` references, which are resolved against the MLflow server's environment during runtime. The resolved secrets are then sent in provider authentication headers to the configured upstream `api_base`. This vulnerability can be exploited by low-privileged authenticated users in basic-auth deployments or by unauthenticated users in default deployments without `basic-auth`. The impact includes potential leakage of sensitive credentials such as cloud artifact credentials (`AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`), which could lead to artifact poisoning and cross-boundary code execution in downstream environments. The issue is fixed in version 3.11.0.

## Affected packages

- `mlflow < 3.11.0`

## Remediation

Upgrade to a patched release:

- `mlflow 3.11.0`