Arbitrary file write via tar traversal in mlflow

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.1 · CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS

• CVE-2025-15031: 0.89% estimated exploitation activity in the next 30 days; percentile 59.52 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

A vulnerability in MLflow's pyfunc extraction process allows for arbitrary file writes due to improper handling of tar archive entries. Specifically, the use of tarfile.extractall without path validation enables crafted tar.gz files containing .. or absolute paths to escape the intended extraction directory. This issue affects the latest version of MLflow and poses a high/critical risk in scenarios involving multi-tenant environments or ingestion of untrusted artifacts, as it can lead to arbitrary file overwrites and potential remote code execution.

Published by the source

19 Mar 2026, 00:30 UTC

Last modified by the source

10 Sep 2026, 03:51 UTC

Source last checked

26 Oct 2026, 13:37 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-fhff-qmm8-h2fp

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-fhff-qmm8-h2fp

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# Patch Next advisory brief: CVE-2025-15031

Advisory: Arbitrary file write via tar traversal in mlflow
IDs: CVE-2025-15031, GHSA-fhff-qmm8-h2fp
Record: https://patchnext.com/advisories/cve-2025-15031 (revision 2, source checked 26 Oct 2026, 13:37 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: mlflow 3.9.0rc0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI mlflow: affected < 3.9.0rc0; fixed in 3.9.0rc0

## Suggested inspection (read-only)
- `python -m pip show mlflow`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on mlflow.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-fhff-qmm8-h2fp (OSV record GHSA-fhff-qmm8-h2fp lists affected ranges: PyPI mlflow >=0 <3.9.0rc0 (fixed))
- Verified: https://github.com/advisories/GHSA-fhff-qmm8-h2fp (GitHub-reviewed advisory GHSA-fhff-qmm8-h2fp lists affected ranges: PyPI mlflow >=0 <3.9.0rc0)

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