CVE-2026-2635

MLflow Use of Default Password Authentication Bypass Vulnerability

At a glance

Severity: HIGH 7.3
EPSS: EPSS 1.08 % · percentile 65 (2026-10-27)
State: PUBLISHED
Published: 2026-02-20
Updated: 2026-07-15
Assigner: zdi
NVD status: Deferred

Description

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.

Scores

Version	Score	Vector	Scored by
CVSS 3.0	CRITICAL 9.8	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	zdi
CVSS 3.1	HIGH 7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L	redhat-SADP
CVSS 3.1	HIGH 7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L	NVD · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c (Secondary)
CVSS 3.0	CRITICAL 9.8	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	NVD · zdi-disclosures@trendmicro.com (Secondary)

Weaknesses (CWE)

Advisories

GHSA-gq3w-7jj3-x7gr — MLflow Use of Default Password Authentication Bypass Vulnerability
PYSEC-2026-421 — MLflow Use of Default Password Authentication Bypass Vulnerability

European references

ENISA EUVD · EUVD-2026-7766
GCVE · GCVE-0-2026-2635

Affected products

Product	Versions
MLflow · MLflow	affected 3.4.0

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD