Pallets Werkzeug before 0.15.3, when used with Docker, has insufficient debugger PIN randomness because Docker containers share the same machine id.
https://palletsprojects.com/blog/werkzeug-0-15-3-released/
https://github.com/pallets/werkzeug/commit/00bc43b1672e662e5e3b8cecd79e67fc968fa246
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00047.html
http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00034.html