CVE-2026-2635 MLflow Use of Default Password Authentication Bypass Vulnerability
Remote attackers can bypass authentication using hard-coded default credentials in MLflow to execute arbitrary code as administrator.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-2635?
CVE-2026-2635 is a critical vulnerability in MLflow, published on 20 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-2635?
3 open source packages ship an affected version, including mlflow.
| Package | Affected | Fixed in |
|---|---|---|
mlflow PyPI | All versions | 3.8.0rc0 |
mlflow PyPI | All versions | 3.8.0rc0 |
mlflow PyPI | All versions | 3.8.0rc0 |
How do I fix CVE-2026-2635?
Upgrade mlflow to 3.8.0rc0 or later.
Is CVE-2026-2635 being exploited?
There is no known exploitation of CVE-2026-2635 in the wild and no public exploit code.
Sources
Also known as GHSA-gq3w-7jj3-x7gr, PYSEC-2026-421.