Django Incorrect Default Permissions Vulnerability - CVE-2019-19118

Django 2.1 before 2.1.15 and 2.2 before 2.2.8 allows unintended model editing. A Django model admin displaying inline related models where the user has view-only permissions to a parent model but edit permissions to the inline model would be presented with an editing UI allowing POST requests for updating the inline model. Directly editing the view-only parent model was not possible but the parent model39s save() method was called triggering potential side effects and causing pre and post-save signal handlers to be invoked. (To resolve this the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.)