Environment Variable Resolution Vulnerability in mlflow/mlflow_CVE-2026-4035

{
    "lastseen": "",
    "description": "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.",
    "published": "2026-06-03T07:18:08.512Z",
    "modified": "2026-06-03T07:18:08.512Z",
    "type": "cve",
    "title": "Environment Variable Resolution Vulnerability in mlflow/mlflow",
    "source": "@huntr_ai",
    "references": "https://huntr.com/bounties/f8e591a0-0f19-4910-b82e-16c9956f2233\nhttps://github.com/mlflow/mlflow/commit/4a3f2f720cb4f058c9e0c5b883e0acc9ab64a7f3",
    "id": "CVE-2026-4035",
    "bulletinFamily": "",
    "cwe": [
        "CWE-201"
    ],
    "cvelist": null,
    "sourceData": "mlflow mlflow/mlflow unspecified",
    "sourceHref": "",
    "cvss": {
        "score": 9.1,
        "severity": "CRITICAL",
        "vector": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:L",
        "version": "3.0"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "mlflow/mlflow",
    "version": "unspecified",
    "vendor": "mlflow",
    "ai_description": "Environment variable resolution vulnerability allowing exfiltration of sensitive server-side environment credentials",
    "ai_severity": "CRITICAL",
    "ai_vendor": "MLflow",
    "ai_product": "mlflow/mlflow",
    "ai_version": "prior to 3.11.0",
    "ai_score": 9.1
}