django/django

===========================
Django 4.1.13 release notes
===========================

*November 1, 2023*

Django 4.1.13 fixes a security issue with severity "moderate" in 4.1.12.

CVE-2023-46695: Potential denial of service vulnerability in ``UsernameField`` on Windows
=========================================================================================

The :func:`NFKC normalization <python:unicodedata.normalize>` is slow on
Windows. As a consequence, ``django.contrib.auth.forms.UsernameField`` was
subject to a potential denial of service attack via certain inputs with a very
large number of Unicode characters.

In order to avoid the vulnerability, invalid values longer than
``UsernameField.max_length`` are no longer normalized, since they cannot pass
validation anyway.