Django: CVE-2021-3281: Potential directory-traversal via archive.extract()

[Mariusz Felisiak <felisiak.mariusz () gmail com>]

https://www.djangoproject.com/weblog/2021/feb/01/security-releases/

In accordance with `our security release policy 
<https://docs.djangoproject.com/en/dev/internals/security/>`_, the 
Django team is issuing
`Django 3.1.6 <https://docs.djangoproject.com/en/dev/releases/3.1.6/>`_,
`Django 3.0.12 
<https://docs.djangoproject.com/en/dev/releases/3.0.12/>`_ and
`Django 2.2.18 <https://docs.djangoproject.com/en/dev/releases/2.2.18/>`_.
These releases address the security issue with severity "low" detailed 
below. We encourage all users of Django to upgrade as soon as possible.

CVE-2021-3281: Potential directory-traversal via ``archive.extract()``
======================================================================

The ``django.utils.archive.extract()`` function, used by
``startapp --template`` and ``startproject --template``, allowed
directory-traversal via an archive with absolute paths or relative paths 
with
dot segments.

Thank you to Wang Baohua for the report.

Affected supported versions
===========================

* Django master branch
* Django 3.2 (currently at alpha status)
* Django 3.1
* Django 3.0
* Django 2.2

Resolution
==========

Patches to resolve the issue have been applied to Django's master branch and
the 3.2, 3.1, 3.0, and 2.2 release branches. The patches may be obtained 
from the following changesets:

* On the `master branch 
<https://github.com/django/django/commit/05413afa8c18cdb978fcdf470e09f7a12b234a23>`__
* On the `3.2 release branch 
<https://github.com/django/django/commit/f944f79e555c91571192022a6bb9ddf2178db7ed>`__
* On the `3.1 release branch 
<https://github.com/django/django/commit/02e6592835b4559909aa3aaaf67988fef435f624>`__
* On the `3.0 release branch 
<https://github.com/django/django/commit/52e409ed17287e9aabda847b6afe58be2fa9f86a>`__
* On the `2.2 release branch 
<https://github.com/django/django/commit/21e7622dec1f8612c85c2fc37fe8efbfd3311e37>`__

The following releases have been issued:

* Django 3.1.6 (`download Django 3.1.6 
<https://www.djangoproject.com/m/releases/3.1/Django-3.1.6.tar.gz>`_ | 
`3.1.6 checksums 
<https://www.djangoproject.com/m/pgp/Django-3.1.6.checksum.txt>`_)
* Django 3.0.12 (`download Django 3.0.12 
<https://www.djangoproject.com/m/releases/3.0/Django-3.0.12.tar.gz>`_ | 
`3.0.12 checksums 
<https://www.djangoproject.com/m/pgp/Django-3.0.12.checksum.txt>`_)
* Django 2.2.18 (`download Django 2.2.18 
<https://www.djangoproject.com/m/releases/2.2/Django-2.2.18.tar.gz>`_ | 
`2.2.18 checksums 
<https://www.djangoproject.com/m/pgp/Django-2.2.18.checksum.txt>`_)

The PGP key ID used for this release is Mariusz Felisiak: 
`2EF56372BA48CD1B <https://github.com/felixxm.gpg>`_.

General notes regarding security reporting
==========================================

As always, we ask that potential security issues be reported via
private email to ``security () djangoproject com``, and not via Django's
Trac instance or the django-developers list. Please see `our security
policies <https://www.djangoproject.com/security/>`_ for further
information.