CVE-2026-8147 is an improper access control vulnerability (CWE-284) in mlflow/mlflow affecting versions before 3.14.0. When authentication is enabled, the trace API endpoints lack proper authorization validation due to missing registration of authorization validators in the _before_request handler. This flaw permits any authenticated user to bypass experiment-level authorization controls and perform unauthorized read, delete, and modify operations on traces of experiments they do not have permission to access. The vulnerability risks exposure of sensitive data, destruction of audit logs, and unauthorized modifications.

The vulnerability allows authenticated users to bypass authorization controls on trace operations, potentially exposing sensitive experiment trace data, enabling deletion or modification of traces, and compromising audit integrity. This can lead to unauthorized data disclosure and tampering within MLflow experiments.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict authenticated user permissions to trusted users only and monitor for suspicious trace API activity. Avoid enabling authentication without additional compensating controls on trace endpoints.