Bug 1252891 - (CVE-2015-5964) CVE-2015-5964 python-django: Denial-of-service possibility in logout() view by filling session store
CVE-2015-5964 python-django: Denial-of-service possibility in logout() view b...
Status: CLOSED ERRATA
Product: Security Response
Classification: Other
Component: vulnerability (Show other bugs)
unspecified
All Linux
medium Severity medium
: ---
: ---
Assigned To: Red Hat Product Security
impact=moderate,public=20150818,repor...
: Security
Depends On: 1254912 1254913 1254914 1254921 1257809 1257810
Blocks: 1252892
  Show dependency treegraph
 
Reported: 2015-08-12 09:06 EDT by Vasyl Kaigorodov
Modified: 2016-11-08 11:21 EST (History)
19 users (show)

See Also:
Fixed In Version:
Doc Type: Bug Fix
Doc Text:
It was found that certain Django functions would, in certain circumstances, create empty sessions. A remote attacker could use this flaw to fill up the session store or cause other users' session records to be evicted by requesting a large number of new sessions.
Story Points: ---
Clone Of:
Environment:
Last Closed: 2015-10-15 19:01:28 EDT
Type: ---
Regression: ---
Mount Type: ---
Documentation: ---
CRM:
Verified Versions:
Category: ---
oVirt Team: ---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---


Attachments (Terms of Use)

  None (edit)
Description Vasyl Kaigorodov 2015-08-12 09:06:00 EDT
Following issue was reported in Django:

In CVE-2015-5963, the ``django.contrib.sessions.middleware.SessionMiddleware`` has been modified to no longer create empty session records.
Additionally, on the 1.4 and 1.7 series only, the ``contrib.sessions.backends.base.SessionBase.flush()`` and ``cache_db.SessionStore.flush()`` methods have been modified to avoid creating a new empty session. 
This modification of 1.4 and 1.7 series got CVE-2015-5964.

Previously, a session could be created when anonymously accessing the ``django.contrib.auth.views.logout`` view (provided it wasn't decorated with ``django.contrib.auth.decorators.login_required`` as done in the admin). This could allow an attacker to easily create many new session records by sending repeated requests, potentially filling up the session store or causing other users' session records to be evicted.
Comment 1 Vasyl Kaigorodov 2015-08-12 09:11:29 EDT
Acknowledgements:

Red Hat would like to thank the upstream Django project for reporting this issue. Upstream acknowledges Lin Hua Cheng as the original reporter.
Comment 2 Adam Mariš 2015-08-19 04:46:49 EDT
Public via:
https://www.djangoproject.com/weblog/2015/aug/18/security-releases/
Comment 3 Adam Mariš 2015-08-19 04:54:07 EDT
Created python-django tracking bugs for this issue:

Affects: fedora-all [bug 1254921]
Comment 7 errata-xmlrpc 2015-09-10 07:44:29 EDT
This issue has been addressed in the following products:

  OpenStack 5 for RHEL 6

Via RHSA-2015:1766 https://rhn.redhat.com/errata/RHSA-2015-1766.html
Comment 8 errata-xmlrpc 2015-09-10 08:06:06 EDT
This issue has been addressed in the following products:

  OpenStack 5 for RHEL 7

Via RHSA-2015:1767 https://rhn.redhat.com/errata/RHSA-2015-1767.html
Comment 9 errata-xmlrpc 2015-10-15 08:35:01 EDT
This issue has been addressed in the following products:

  OpenStack 6 for RHEL 7

Via RHSA-2015:1894 https://rhn.redhat.com/errata/RHSA-2015-1894.html

Note You need to log in before you can comment on or make changes to this bug.