CVE-2025-15036: MLflow: path traversal enables sandbox escape, file overwrite

GHSA-vhcx-3pq2-4fvc CRITICAL CISA: ATTEND
Published March 30, 2026
CISO Take

MLflow versions before v3.7.0 allow an attacker who controls a tar.gz artifact to overwrite arbitrary files and potentially escape the sandbox in multi-tenant or shared cluster environments (e.g., Databricks Connect). If your ML platform ingests user-supplied or third-party model artifacts via MLflow, treat this as HIGH severity and patch to v3.7.0 immediately. In shared environments where multiple teams or tenants load artifacts, this is a lateral movement and privilege escalation vector—prioritize accordingly.

What is the risk?

Although no CVSS score has been assigned yet, this vulnerability carries high effective risk in enterprise MLOps environments. The exploit primitive—crafting a malicious tar.gz—is trivial and well-documented. Impact is severe in multi-tenant ML platforms where sandbox isolation is a security boundary. Single-tenant, air-gapped deployments where artifact provenance is tightly controlled face lower—but not zero—risk. The absence of CISA KEV listing and EPSS score reflects recency, not low severity. Shared cluster environments using Databricks Connect are the highest-risk deployment pattern.

What systems are affected?

Package Ecosystem Vulnerable Range Patched
mlflow pip < 3.9.0rc0 3.9.0rc0
25.8K OpenSSF 4.7 624 dependents Pushed 4d ago 23% patched ~64d to patch Full package profile →

Do you use mlflow? You're affected.

Severity & Risk

CVSS 3.1
9.6 / 10
EPSS
0.0%
chance of exploitation in 30 days
Higher than 11% of all CVEs
Exploitation Status
Exploit Available
Exploitation: MEDIUM
Sophistication
Trivial
Exploitation Confidence
medium
CISA SSVC: Public PoC
Composite signal derived from CISA KEV, CISA SSVC, EPSS, trickest/cve, and Nuclei templates.

Attack Surface

AV AC PR UI S C I A
AV Network
AC Low
PR None
UI Required
S Changed
C High
I High
A High

What should I do?

5 steps
  1. PATCH

    Upgrade MLflow to v3.7.0 or later immediately—this is the definitive fix. Reference commit: 3bf6d81ac4d38654c8ff012dbd0c3e9f17e7e346.

  2. VERIFY PROVENANCE

    Until patched, enforce strict provenance controls on all tar.gz artifacts ingested by MLflow—only accept artifacts from trusted, cryptographically signed sources.

  3. RESTRICT ARTIFACT SOURCES

    Disable ingestion of externally-sourced model artifacts in multi-tenant clusters if patching is delayed.

  4. DETECT

    Search logs for unexpected file writes outside expected MLflow working directories during artifact extraction. Monitor for new files created in /etc, /usr, or home directories during MLflow model load operations.

  5. AUDIT DEPLOYMENTS

    Identify all Databricks Connect and MLflow deployments using dbconnect_artifact_cache—prioritize shared/multi-tenant clusters.

CISA SSVC Assessment

Decision Attend
Exploitation poc
Automatable No
Technical Impact total

Source: CISA Vulnrichment (SSVC v2.0). Decision based on the CISA Coordinator decision tree.

Classification

Compliance Impact

This CVE is relevant to:

EU AI Act
Article 9 - Risk management system
ISO 42001
6.1.2 - AI risk assessment 8.4 - AI system operation
NIST AI RMF
MANAGE-2.2 - Mechanisms to sustain treatment of identified risks
OWASP LLM Top 10
LLM05:2025 - Vulnerable Supply Chain

Frequently Asked Questions

What is CVE-2025-15036?

MLflow versions before v3.7.0 allow an attacker who controls a tar.gz artifact to overwrite arbitrary files and potentially escape the sandbox in multi-tenant or shared cluster environments (e.g., Databricks Connect). If your ML platform ingests user-supplied or third-party model artifacts via MLflow, treat this as HIGH severity and patch to v3.7.0 immediately. In shared environments where multiple teams or tenants load artifacts, this is a lateral movement and privilege escalation vector—prioritize accordingly.

Is CVE-2025-15036 actively exploited?

No confirmed active exploitation of CVE-2025-15036 has been reported, but organizations should still patch proactively.

How to fix CVE-2025-15036?

1. PATCH: Upgrade MLflow to v3.7.0 or later immediately—this is the definitive fix. Reference commit: 3bf6d81ac4d38654c8ff012dbd0c3e9f17e7e346. 2. VERIFY PROVENANCE: Until patched, enforce strict provenance controls on all tar.gz artifacts ingested by MLflow—only accept artifacts from trusted, cryptographically signed sources. 3. RESTRICT ARTIFACT SOURCES: Disable ingestion of externally-sourced model artifacts in multi-tenant clusters if patching is delayed. 4. DETECT: Search logs for unexpected file writes outside expected MLflow working directories during artifact extraction. Monitor for new files created in /etc, /usr, or home directories during MLflow model load operations. 5. AUDIT DEPLOYMENTS: Identify all Databricks Connect and MLflow deployments using `dbconnect_artifact_cache`—prioritize shared/multi-tenant clusters.

What systems are affected by CVE-2025-15036?

This vulnerability affects the following AI/ML architecture patterns: Training pipelines, MLOps platforms, Model serving, Multi-tenant ML environments, CI/CD ML pipelines.

What is the CVSS score for CVE-2025-15036?

CVE-2025-15036 has a CVSS v3.1 base score of 9.6 (CRITICAL). The EPSS exploitation probability is 0.04%.

Technical Details

NVD Description

A path traversal vulnerability exists in the `extract_archive_to_dir` function within the `mlflow/pyfunc/dbconnect_artifact_cache.py` file of the mlflow/mlflow repository. This vulnerability, present in versions before v3.7.0, arises due to the lack of validation of tar member paths during extraction. An attacker with control over the tar.gz file can exploit this issue to overwrite arbitrary files or gain elevated privileges, potentially escaping the sandbox directory in multi-tenant or shared cluster environments.

Exploitation Scenario

An attacker operating in a multi-tenant ML environment (e.g., a shared Databricks workspace) crafts a malicious tar.gz file containing path traversal sequences in member filenames (e.g., `../../etc/cron.d/backdoor`). They publish this as a model artifact to a shared MLflow Model Registry—either by compromising a low-privilege account, exploiting a misconfigured registry, or via a poisoned upstream dependency. When a victim user or automated pipeline loads the model via `mlflow.pyfunc.load_model()`, MLflow's artifact cache mechanism extracts the tar.gz without validating member paths. The malicious file is written outside the sandbox directory, potentially overwriting a cron job, SSH authorized_keys, or Python site-packages to achieve persistent code execution with elevated privileges on the shared cluster.

CVSS Vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

Timeline

Published
March 30, 2026
Last Modified
April 1, 2026
First Seen
March 30, 2026

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