---
id: CVE-2026-2635
title: MLflow Use of Default Password Authentication Bypass Vulnerability
summary: >-
  MLflow Use of Default Password Authentication Bypass Vulnerability. This
  vulnerability allows remote attackers to bypass authentication on affected
  installations of MLflow. Authentication is not required to exploit this
  vulnerability.


  T…
severity: high
cvss: 7.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L'
cwe:
  - CWE-1393
  - CWE-798
vendor: MLflow
product: MLflow
affected:
  - MLflow 3.4.0
published: '2026-02-20'
updated: '2026-07-15'
sourceUpdated: '2026-07-15T02:19:32.480'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-2635'
references:
  - url: 'https://github.com/mlflow/mlflow/pull/19260'
    label: zdi-disclosures@trendmicro.com
  - url: 'https://www.zerodayinitiative.com/advisories/ZDI-26-111/'
    label: zdi-disclosures@trendmicro.com
  - url: 'https://access.redhat.com/security/cve/CVE-2026-2635'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2441514'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2635.json
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
tags:
  - nvd
  - cve.org
  - score-dispute
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-02-26T00:00:00+00:00'
scores:
  nvd: 7.3
  cna: 9.8
ingestedAt: '2026-09-13T09:36:14.952Z'
epss: 0.01215
epssPercentile: 0.67285
zeroDay: true
---

## Overview

MLflow Use of Default Password Authentication Bypass Vulnerability. This vulnerability allows remote attackers to bypass authentication on affected installations of MLflow. Authentication is not required to exploit this vulnerability.

The specific flaw exists within the basic_auth.ini file. The file contains hard-coded default credentials. An attacker can leverage this vulnerability to bypass authentication and execute arbitrary code in the context of the administrator. Was ZDI-CAN-28256.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.