CVE-2026-2734: Authorization Bypass in SearchModelVersions in mlflow/mlflow
In mlflow/mlflow versions up to 3.9.0, the SearchModelVersions REST API endpoint and the mlflowSearchModelVersions GraphQL query lack proper per-model authorization checks when basic authentication is enabled. This allows any authenticated user to enumerate all model versions across all registered models, regardless of their permission level. The issue arises due to the absence of SearchModelVersions in the BEFOREREQUESTVALIDATORS and AFTERREQUESTHANDLERS for the REST API, and its omission from GraphQLAuthorizationMiddleware.PROTECTEDFIELDS for GraphQL. This vulnerability can expose sensitive information such as model names, version descriptions, source URIs, tags, and other metadata, potentially revealing proprietary or confidential details in multi-tenant environments. The issue is resolved in version 3.10.0.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
mlflow/mlflowto a version that resolves this vulnerability.Fixed in 3.10.0
Event History
Frequently Asked Questions
What is the severity of CVE-2026-2734?
CVE-2026-2734 is considered a high severity vulnerability due to the potential for unauthorized access to model versions.
How do I fix CVE-2026-2734?
To mitigate CVE-2026-2734, upgrade to mlflow version 3.10.0 or later which includes proper authorization checks.
What systems are affected by CVE-2026-2734?
CVE-2026-2734 affects mlflow versions up to and including 3.9.0.
What type of vulnerability is CVE-2026-2734?
CVE-2026-2734 is an authorization bypass vulnerability that allows unauthorized users to access certain model versions.
Is basic authentication safe with CVE-2026-2734?
Basic authentication is not safe with CVE-2026-2734 as it lacks per-model authorization checks in the affected versions.