The authentication framework (django.contrib.auth) in Django 1.4.x before 1.4.8, 1.5.x before 1.5.4, and 1.6.x before 1.6 beta 4 allows remote attackers to cause a denial of service (CPU consumption) via a long password which is then hashed.
https://www.djangoproject.com/weblog/2013/sep/15/security/
http://www.debian.org/security/2013/dsa-2758
http://python.6.x6.nabble.com/Set-a-reasonable-upper-bound-on-password-length-td5032218.html
http://lists.opensuse.org/opensuse-updates/2013-11/msg00035.html
http://lists.opensuse.org/opensuse-updates/2013-10/msg00015.html