An issue was discovered in Django 1.11 before 1.11.22, 2.1 before 2.1.10, and 2.2 before 2.2.3. An HTTP request is not redirected to HTTPS when the SECURE_PROXY_SSL_HEADER and SECURE_SSL_REDIRECT settings are used, and the proxy connects to Django via HTTPS. In other words, django.http.HttpRequest.scheme has incorrect behavior when a client uses HTTP.
https://www.djangoproject.com/weblog/2019/jul/01/security-releases/
https://www.debian.org/security/2019/dsa-4476
https://usn.ubuntu.com/4043-1/
https://security.netapp.com/advisory/ntap-20190705-0002/
https://seclists.org/bugtraq/2019/Jul/10
https://groups.google.com/forum/#%21topic/django-announce/Is4kLY9ZcZQ
https://docs.djangoproject.com/en/dev/releases/security/
http://www.securityfocus.com/bid/109018
http://www.openwall.com/lists/oss-security/2019/07/01/3
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00025.html
http://lists.opensuse.org/opensuse-security-announce/2019-08/msg00006.html