Apache Airflow's public Import Errors API returns the raw parse-failure stack trace to any user with the "ImportError.can_read" permission when the failing file has no registered DAG. This happens when a file fails to parse before any DAG is defined, or when all of its previously registered DAGs are removed but the parse error remains. Users who should not see that file's details can read stack traces that may expose file paths and code. Users are advised to upgrade to Apache Airflow 3.4.0 or later, which restricts these stack traces to users with the new "IMPORT_ERRORS_ALL" permission.