In Django 1.11.x before 1.11.18, 2.0.x before 2.0.10, and 2.1.x before 2.1.5, an Improper Neutralization of Special Elements in Output Used by a Downstream Component issue exists in django.views.defaults.page_not_found(), leading to content spoofing

Django 1.11.x before 1.11.19, 2.0.x before 2.0.11, and 2.1.x before 2.1.6 allows Uncontrolled Memory Consumption via a malicious attacker-supplied value to the django.utils.numberformat.format() function.