MLflow: trace API endpoints lack proper authorization validators
High8.1CVE-2026-8147 · Published Jul 2, 2026 · updated Aug 19, 2026
In MLflow versions prior to 3.13.0, when running with authentication enabled, the trace API endpoints lack proper authorization validators. This allows any authenticated user to bypass experiment-level authorization controls on all trace operations, including reading, deleting, and modifying traces on experiments they do not have permission to access. The issue arises from the `_before_request` handler, which does not register authorization validators for trace endpoints, resulting in requests proceeding without validation. This vulnerability can expose sensitive data, destroy audit logs, and allow unauthorized modifications.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| mlflow PyPI | >= 2.14.0rc0, < 3.13.0rc0 | 3.13.0rc0 |
Details and references
- CVSS 3.0
- CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
- Severity from
- GitHub (reviewed advisory)
- Weakness
- CWE-284
- Also known as
- BIT-mlflow-2026-8147, CVE-2026-8147, PYSEC-2026-3686
More MLflow advisories
All MLflow| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Aug 5 | MLflow AI Gateway permits SSRF through an unvalidated api_base | High7.1 | No fix yet |
| Jun 4 | MLflow: Deterministic sampling in dataset digest enables predictable collisions | Low3.6 | 3.10.1 |
| Jun 3 | MLflow: Environment variable injection in AI Gateway secrets enables server-side credential exfiltration | Critical9.1 | 3.11.0 |
| Jun 2 | MLflow: Any authenticated user can enumerate all gateway secrets, endpoints, and model definitions | Medium6.5 | 3.11.0rc0 |
| May 26 | MLflow allows unauthorized access to multipart upload endpoints when the `--serve-artifacts` mode is enabled | Critical9.0 | 3.11.0rc1 |
| May 21 | MLflow: information disclosure | Medium6.5 | 3.10.0 |