In Apache Airflow prior to 2.2.0. This CVE applies to a specific case where a User who has "can_create" permissions on DAG Runs can create Dag Runs for dags that they don't have "edit" permissions for.
If remote logging is not used, the worker (in the case of CeleryExecutor) or the scheduler (in the case of LocalExecutor) runs a Flask logging server and is listening on a specific port and also binds on 0.0.0.0 by default. This logging server had no authentication and allows reading log files of DAG jobs. This issue affects Apache Airflow < 2.1.2.