GHSA-2f9x-5v75-3qv4 Django Denial-of-service possibility in truncatechars_html and truncatewords_html template filters

• PyPI Django: >= 2.0, < 2.0.3 → fixed in 2.0.3 • PyPI Django: >= 1.11, < 1.11.11 → fixed in 1.11.11 • PyPI Django: >= 1.8, < 1.8.19 → fixed in 1.8.19

An issue was discovered in Django 2.0 before 2.0.3, 1.11 before 1.11.11, and 1.8 before 1.8.19. 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 truncatechars_html and truncatewords_html template filters, which were thus vulnerable.