Authentication Bypass in mlflow/mlflow (mlflow mlflow/mlflow)
At a glance
- Source
- NVD
- EPSS
- EPSS 20.78 % · percentile 98 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- @huntr_ai
- NVD status
- Analyzed
Description
A vulnerability in mlflow/mlflow versions 3.9.0 and earlier allows unauthenticated access to certain FastAPI routes when the server is started with authentication enabled (`--app-name basic-auth`) and served via uvicorn (ASGI). The FastAPI permission middleware only enforces authentication on `/gateway/` routes, leaving other routes such as the Job API (`/ajax-api/3.0/jobs/*`) and the OpenTelemetry trace ingestion API (`/v1/traces`) unprotected. This allows unauthenticated remote attackers to submit jobs, read job results, cancel running jobs, and inject arbitrary trace data into experiments. The issue arises from an architectural mismatch between Flask and FastAPI authentication mechanisms, where the `_find_fastapi_validator()` function fails to handle non-`/gateway/` paths, resulting in a complete authentication bypass. This vulnerability is fixed in version 3.10.0.
Weaknesses (CWE)
- CWE-305 — Authentication Bypass by Primary Weakness
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.0 | HIGH 8.6 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L | @huntr_ai |
| CVSS 3.0 | HIGH 8.6 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:L | NVD · security@huntr.dev (Secondary) |
Advisories
- GHSA-75cm-x2w3-8mgf — MLflow: unauthenticated access to certain FastAPI routes
- PYSEC-2026-2221 — A vulnerability in mlflow/mlflow versions 3.9.0 and earlier allows unauthenticated access to certain FastAPI routes when the server is started with authenticati
European references
- ENISA EUVD · EUVD-2026-30499
- GCVE · GCVE-0-2026-2652
Affected configurations (NVD CPE)
cpe:2.3:a:lfprojects:mlflow:*:*:*:*:*:*:*:*< 3.10.0
Affected products
| Product | Versions |
|---|---|
| mlflow · mlflow/mlflow | affected unspecified < 3.10.0 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |