Server-side Request Forgery (SSRF) Affecting mlflow package, versions [,3.15.0)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

Exploit Maturity
Attacked
EPSS
16.41% (97th percentile)

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  • Snyk IDSNYK-PYTHON-MLFLOW-18912142
  • published18 Aug 2026
  • disclosed17 Aug 2026
  • creditYo Iida, Ievgen Bondarenko, Katika Mohaseen, Mayur Parmar

Introduced: 17 Aug 2026

NewCVE-2026-64849  (opens in a new tab)
CWE-918  (opens in a new tab)

How to fix?

Upgrade mlflow to version 3.15.0 or higher.

Overview

mlflow is a platform to streamline machine learning development, including tracking experiments, packaging code into reproducible runs, and sharing and deploying models.

Affected versions of this package are vulnerable to Server-side Request Forgery (SSRF) via a DNS rebinding attack against the webhook delivery mechanism in mlflow/webhooks/delivery.py. The original SSRF protection in _validate_webhook_url resolves the webhook hostname and checks that all resolved IPs are public, but then discards the resolved address; the subsequent requests.post call re-resolves the hostname independently. This TOCTOU gap allows an attacker to return a public IP during validation and a private or link-local IP (e.g., 169.254.169.254) at actual request time, enabling unauthenticated access to cloud metadata services or internal network resources. No authentication or user interaction is required.

CVSS Base Scores

version 4.0
version 3.1