# Django 4.0.11.dev20230214085346 documentation

# Django 3.0.1 release notes

December 18, 2019

Django 3.0.1 fixes a security issue and several bugs in 3.0.

## CVE-2019-19844: Potential account hijack via password reset form

By submitting a suitably crafted email address making use of Unicode characters, that compared equal to an existing user email when lower-cased for comparison, an attacker could be sent a password reset token for the matched account.

In order to avoid this vulnerability, password reset requests now compare the submitted email using the stricter, recommended algorithm for case-insensitive comparison of two identifiers from Unicode Technical Report 36, section 2.11.2(B)(2). Upon a match, the email containing the reset token will be sent to the email address on record rather than the submitted address.

## Bugfixes

- Fixed a regression in Django 3.0 by restoring the ability to use Django inside Jupyter and other environments that force an async context, by adding an option to disable Async safety mechanism with `DJANGO_ALLOW_ASYNC_UNSAFE` environment variable (#31056).
- Fixed a regression in Django 3.0 where `RegexPattern`, used by `re_path()`, returned positional arguments to be passed to the view when all optional named groups were missing (#31061).
- Reallowed, following a regression in Django 3.0, `Window` expressions to be used in conditions outside of queryset filters, e.g. in `When` conditions (#31060).
- Fixed a data loss possibility in `SplitArrayField`. When using with `ArrayField(BooleanField())`, all values after the first `True` value were marked as checked instead of preserving passed values (#31073).