[5.1.x] Fixed CVE-2024-45230 -- Mitigated potential DoS in urlize and urlizetrunc template filters.

Thanks MProgrammer (https://hackerone.com/mprogrammer) for the report.

docs/ref/templates/builtins.txt

@@ -2932,6 +2932,17 @@ Django's built-in :tfilter:`escape` filter. The default value for
     email addresses that contain single quotes (``'``), things won't work as
     expected. Apply this filter only to plain text.
 
+.. warning::
+
+    Using ``urlize`` or ``urlizetrunc`` can incur a performance penalty, which
+    can become severe when applied to user controlled values such as content
+    stored in a :class:`~django.db.models.TextField`. You can use
+    :tfilter:`truncatechars` to add a limit to such inputs:
+
+    .. code-block:: html+django
+
+        {{ value|truncatechars:500|urlize }}
+
 .. templatefilter:: urlizetrunc
 
 ``urlizetrunc``