MLflow: Unauthenticated full-read SSRF in webhook delivery: _validate_webhook_url bypassed via unvalidated HTTP redirects (and DNS rebinding)

Summary

CVE	CVE-2026-64849
State	PUBLISHED
Assigner	GitHub_M
Source Priority	CVE Program / NVD first with legacy fallback
Published	2026-08-17 22:17:23 UTC
Updated	2026-08-20 19:16:57 UTC
Description	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.

Primary CVSS: v3.1 9.3 CRITICAL from [email protected]

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N

EPSS: 0.164100000 probability, percentile 0.967550000 (date 2026-09-02)

CISA KEV: Listed on 2026-08-19; due 2026-09-02; ransomware use Unknown

Problem Types: CWE-918 | CWE-918 CWE-918: Server-Side Request Forgery (SSRF)

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Secondary	9.3	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N`
3.1	CNA	DECLARED	9.3	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N`

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

High

Integrity

Low

Availability

None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N

Vendor	MLflow
Product	MLflow
Name	MLflow Server-Side Request Forgery Vulnerability
Required Action	Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Notes	https://github.com/mlflow/mlflow/pull/24258 ; https://github.com/mlflow/mlflow/issues/24179 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2026-64849

Type	Vendor	Product	Version	Update	Edition	Language
Application	Lfprojects	Mlflow	All	All	All	All

Source	Vendor	Product	Version	Platforms
CNA	Mlflow	Mlflow	affected < 3.15.0	Not specified

Reference	Source	Link	Tags
github.com/mlflow/mlflow/commit/ba949522477cbd5915aa55d29b0cfad7d5ddf939	[email protected]	github.com	Patch
github.com/mlflow/mlflow/releases/tag/v3.15.0	[email protected]	github.com	Release Notes
github.com/mlflow/mlflow/issues/24179	[email protected]	github.com	Exploit, Issue Tracking, Mitigation
github.com/mlflow/mlflow/security/advisories/GHSA-7gwp-5pfp-969j	[email protected]	github.com	Exploit, Vendor Advisory
www.cisa.gov/known-exploited-vulnerabilities-catalog	134c704f-9b21-4f2e-91b3-4a467353bcc0	www.cisa.gov	US Government Resource
github.com/mlflow/mlflow/pull/24258	[email protected]	github.com	Issue Tracking, Patch
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis
CISA Known Exploited Vulnerabilities catalog	CISA	www.cisa.gov	kev

No vendor comments have been submitted for this CVE.

There are currently no legacy QID mappings associated with this CVE.