*Description*: 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*. *Mitigation*: Use remote logging with GCS, S3, Elasticsearch etc. This is recommended for production environments. And do not publicly expose any other ports apart from Webserver port, Flower port etc. *Credit*: Apache Airflow would like to thank Dolev Farhi for reporting this issue.
