In Django 3.2 before 3.2.21, 4.1 before 4.1.11, and 4.2 before 4.2.5, django.utils.encoding.uri_to_iri() is subject to a potential DoS (denial of service) attack via certain inputs with a very large number of Unicode characters.
https://www.djangoproject.com/weblog/2023/sep/04/security-releases/
https://security.netapp.com/advisory/ntap-20231214-0002/