CVE-2026-4137
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk9th percentile - higher than 9% of all known CVEs
Summary
In mlflow/mlflow prior to version 3.11.0, functions creating temporary directories set insecure permissions (0o777 and 0o770). This allows a local attacker to tamper with model artifacts, leading to arbitrary code execution upon deserialization via cloudpickle.
Risk Assessment
The risk is especially high in environments with shared NFS mounts (e.g., Databricks), where an attacker can gain system control by replacing model files.
Recommendation
Immediately upgrade mlflow/mlflow to version 3.11.0 or later and restrict temporary directory permissions.
Other vulnerabilities in mlflow
See all- CVE-2026-2393High
A Server-Side Request Forgery (SSRF) vulnerability exists in MLflow versions prior to 3.9.0. The `_create_webhook()` function accepts a user-controlled `url` parameter without validation, allowing an attacker to force the MLflow backend to send HTTP requests to internal services or arbitrary external servers.
- CVE-2026-64849CriticalActively exploited
MLflow is an open source AI engineering platform for agents, large language models, and machine learning models. Prior to 3.15.0, the unauthenticated POST /api/2.0/mlflow/webhooks/{id}/test endpoint calls _validate_webhook_url() in mlflow/utils/validation.py only for the original URL while mlflow/webhooks/delivery.py follows redirects and re-resolves the hostname without pinning the validated address, allowing attackers to reach internal or cloud metadata services and receive response_status and response_body. This issue is fixed in version 3.15.0.
- CVE-2026-2651Critical
A vulnerability in MLflow versions up to 3.10.1.dev0 allows unauthorized access to multipart upload (MPU) endpoints when `--serve-artifacts` mode is enabled. The authorization logic does not enforce resource-level permission checks for `/mlflow-artifacts/mpu/*` endpoints, enabling attackers to overwrite artifacts belonging to other users. This can lead to unauthorized cross-user writes, model supply chain poisoning, and arbitrary code execution when compromised models are loaded.
- CVE-2026-2611Critical
In MLflow version 3.9.0, the MLflow Assistant feature introduced improper origin validation in its /ajax-api endpoints. This vulnerability allows a remote attacker to exploit cross-origin requests from a malicious webpage to interact with the MLflow Assistant running on a victim's local machine.
- CVE-2026-0545Critical
In mlflow/mlflow, the FastAPI job endpoints under `/ajax-api/3.0/jobs/*` are not protected by authentication or authorization when the `basic-auth` app is enabled. Even with basic authentication enabled, any network client can submit, read, search, and cancel jobs without credentials.
- CVE-2025-15379Critical
A command injection vulnerability exists in MLflow version 3.8.0 in the model serving container initialization code. The `_install_model_dependencies_to_env()` function directly interpolates dependencies from the `python_env.yaml` file into a shell command without sanitization, allowing an attacker to execute arbitrary commands by supplying a malicious model artifact.
- CVE-2025-15036Critical
A path traversal vulnerability exists in the `extract_archive_to_dir` function of mlflow before version 3.7.0. Lack of tar member path validation allows an attacker to overwrite arbitrary files or escalate privileges.
- CVE-2025-15031Critical
A vulnerability in MLflow's pyfunc extraction process allows arbitrary file writes due to improper handling of tar archive entries. The use of `tarfile.extractall` without path validation enables crafted tar.gz files containing `..` or absolute paths to escape the intended extraction directory.
- CVE-2026-79721High
Code execution can occur in versions of the MLflow platform running version 0.0.1 or newer, enabling a maliciously crafted model artifact to execute arbitrary code on an end user's system when loaded by the project.
- CVE-2026-69148High
MLflow prior to 3.15.0 allows authenticated users to create a model version referencing another user's artifact directory and read files without the required READ permission.
Original NVD description (English source)
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.