========================== Django 2.2.4 release notes ========================== *August 1, 2019* Django 2.2.4 fixes security issues and several bugs in 2.2.3. CVE-2019-14232: Denial-of-service possibility in ``django.utils.text.Truncator`` ================================================================================ If ``django.utils.text.Truncator``'s ``chars()`` and ``words()`` methods were passed the ``html=True`` argument, they were extremely slow to evaluate certain inputs due to a catastrophic backtracking vulnerability in a regular expression. The ``chars()`` and ``words()`` methods are used to implement the :tfilter:`truncatechars_html` and :tfilter:`truncatewords_html` template filters, which were thus vulnerable. The regular expressions used by ``Truncator`` have been simplified in order to avoid potential backtracking issues. As a consequence, trailing punctuation may now at times be included in the truncated output. CVE-2019-14233: Denial-of-service possibility in ``strip_tags()`` ================================================================= Due to the behavior of the underlying ``HTMLParser``, :func:`django.utils.html.strip_tags` would be extremely slow to evaluate certain inputs containing large sequences of nested incomplete HTML entities. The ``strip_tags()`` method is used to implement the corresponding :tfilter:`striptags` template filter, which was thus also vulnerable. ``strip_tags()`` now avoids recursive calls to ``HTMLParser`` when progress removing tags, but necessarily incomplete HTML entities, stops being made. Remember that absolutely NO guarantee is provided about the results of ``strip_tags()`` being HTML safe. So NEVER mark safe the result of a ``strip_tags()`` call without escaping it first, for example with :func:`django.utils.html.escape`. CVE-2019-14234: SQL injection possibility in key and index lookups for ``JSONField``/``HStoreField`` ==================================================================================================== :lookup:`Key and index lookups ` for ``django.contrib.postgres.fields.JSONField`` and :lookup:`key lookups ` for :class:`~django.contrib.postgres.fields.HStoreField` were subject to SQL injection, using a suitably crafted dictionary, with dictionary expansion, as the ``**kwargs`` passed to ``QuerySet.filter()``. CVE-2019-14235: Potential memory exhaustion in ``django.utils.encoding.uri_to_iri()`` ===================================================================================== If passed certain inputs, :func:`django.utils.encoding.uri_to_iri` could lead to significant memory usage due to excessive recursion when re-percent-encoding invalid UTF-8 octet sequences. ``uri_to_iri()`` now avoids recursion when re-percent-encoding invalid UTF-8 octet sequences. Bugfixes ======== * Fixed a regression in Django 2.2 when ordering a ``QuerySet.union()``, ``intersection()``, or ``difference()`` by a field type present more than once results in the wrong ordering being used (:ticket:`30628`). * Fixed a migration crash on PostgreSQL when adding a check constraint with a ``contains`` lookup on :class:`~django.contrib.postgres.fields.DateRangeField` or :class:`~django.contrib.postgres.fields.DateTimeRangeField`, if the right hand side of an expression is the same type (:ticket:`30621`). * Fixed a regression in Django 2.2 where auto-reloader crashes if a file path contains nulls characters (``'\x00'``) (:ticket:`30506`). * Fixed a regression in Django 2.2 where auto-reloader crashes if a translation directory cannot be resolved (:ticket:`30647`).