Bug 915177 (CVE-2023-43665) – <dev-python/django-{4.2.6,4.1.12,3.2.22}: Denial-of-service possibility in ``django.utils.text.Truncator``

• Product: Gentoo Security
• Status: RESOLVED FIXED

[Description Michał Górny 2023-10-04 16:51:10 UTC]

CVE-2023-43665: Denial-of-service possibility in ``django.utils.text.Truncator``
===============================================================================

Following the fix for :cve:`2019-14232`, the regular expressions used in the
implementation of ``django.utils.text.Truncator``'s ``chars()`` and ``words()``
methods (with ``html=True``) were revised and improved. However, these regular
expressions still exhibited linear backtracking complexity, so when given a
very long, potentially malformed HTML input, the evaluation would still be
slow, leading to a potential denial of service vulnerability.

The ``chars()`` and ``words()`` methods are used to implement the
:tfilter:`truncatechars_html` and :tfilter:`truncatewords_html` template
filters, which were thus also vulnerable.

The input processed by ``Truncator``, when operating in HTML mode, has been
limited to the first five million characters in order to avoid potential
performance and memory issues.

[Comment 1 Michał Górny 2023-10-04 18:37:16 UTC]

cleanup done.

[Comment 2 Hans de Graaff 2023-10-05 06:23:46 UTC]

Thanks for the quick action.

GLSA vote: no.