GitHub Advisoryadvisory · PyPI

GHSA-f2m9-wcf4-cwwx MLFlow Creates a Temporary File With Insecure Permissions

HIGH Published 2026-05-18 Modified 2026-09-01 Official page ↗
Aliases
CVE-2026-4137
Ecosystem
PyPI
Packages
mlflow
Severity
High
CVSS vector
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Weaknesses
CWE-378
Reviewed
2026-05-29

Affected packages

• PyPI mlflow: >= 1.26.0, < 3.11.0 → fixed in 3.11.0

Description

In mlflow/mlflow versions prior to 3.11.0, the `get_or_create_nfs_tmp_dir()` function in `mlflow/utils/file_utils.py` creates temporary directories with world-writable permissions (0o777), and the `_create_model_downloading_tmp_dir()` function in `mlflow/pyfunc/__init__.py` creates directories with group-writable permissions (0o770). These insecure permissions allow local attackers to tamper with model artifacts, such as cloudpickle-serialized Python objects, and achieve arbitrary code execution when the tampered artifacts are deserialized via `cloudpickle.load()`. This vulnerability is particularly critical in environments with shared NFS mounts, such as Databricks, where NFS is enabled by default. The issue is a continuation of the vulnerability class addressed in CVE-2025-10279, which was only partially fixed.

Related

Alias · CVE (1)

  • CVE-2026-4137 In mlflow/mlflow versions prior to 3.11.0, the `get_or_create_nfs_tmp_dir()` function in `mlflow/utils/file_utils.py` creates temporary… vulnerability

Weakness · CWE (1)

  • CWE-378 Creation of Temporary File With Insecure Permissions weakness

References