USN-2469-2: Django regression

USN-2469-1 fixed vulnerabilities in Django. The security fix for
CVE-2015-0221 introduced a regression on Ubuntu 10.04 LTS and Ubuntu 12.04
LTS when serving static content through GZipMiddleware. This update fixes
the problem.

We apologize for the inconvenience.

Original advisory details:

Jedediah Smith discovered that Django incorrectly handled underscores in
WSGI headers. A remote attacker could possibly use this issue to spoof
headers in certain environments. (CVE-2015-0219)

Mikko Ohtamaa discovered that Django incorrectly handled user-supplied
redirect URLs. A remote attacker could possibly use this issue to perform a
cross-site scripting attack. (CVE-2015-0220)

Alex Gaynor discovered that Django incorrectly handled reading files in
django.views.static.serve(). A remote attacker could possibly use this
issue to cause Django to consume resources, resulting in a denial of
service. (CVE-2015-0221)

Keryn Knight discovered that Django incorrectly handled forms with
ModelMultipleChoiceField. A remote attacker could possibly use this issue
to cause a large number of SQL queries, resulting in a database denial of
service. This issue only affected Ubuntu 14.04 LTS and Ubuntu 14.10.
(CVE-2015-0222)