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 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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/mlflow/mlflow/commit/1dcbb0c2fbd1f446c328830e601ca13a28219b8a	Patch
https://huntr.com/bounties/648dc30b-76c7-4433-86b8-f43d926fd8d6	Exploit Third Party Advisory
https://huntr.com/bounties/648dc30b-76c7-4433-86b8-f43d926fd8d6	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:lfprojects:mlflow:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-18 21:16

Updated : 2026-07-24 12:10

NVD link : CVE-2026-4137

Mitre link : CVE-2026-4137

CVE.ORG link : CVE-2026-4137

JSON object : View

Products Affected

lfprojects

mlflow

CWE

CWE-378

Creation of Temporary File With Insecure Permissions

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