Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
Browse files

[1.6.x] Fixed #21002 -- Documented JSON session serialization require…

…s string keys

Thanks jeroen.pulles at redslider.net for the report.

Backport of 3baf1d1 from master
  • Loading branch information...
commit c0fb6bdde3ffcfc4108d865cdc3f34a7175e5907 1 parent b53ce2f
@timgraham timgraham authored
Showing with 22 additions and 5 deletions.
  1. +5 −2 docs/releases/1.6.txt
  2. +17 −3 docs/topics/http/sessions.txt
View
7 docs/releases/1.6.txt
@@ -745,7 +745,8 @@ Default session serialization switched to JSON
Historically, :mod:`django.contrib.sessions` used :mod:`pickle` to serialize
session data before storing it in the backend. If you're using the :ref:`signed
cookie session backend<cookie-session-backend>` and :setting:`SECRET_KEY` is
-known by an attacker, the attacker could insert a string into his session
+known by an attacker (there isn't an inherent vulnerability in Django that
+would cause it to leak), the attacker could insert a string into his session
which, when unpickled, executes arbitrary code on the server. The technique for
doing so is simple and easily available on the internet. Although the cookie
session storage signs the cookie-stored data to prevent tampering, a
@@ -759,7 +760,9 @@ For backwards compatibility, this setting defaulted to using :mod:`pickle`
in Django 1.5.3, but we've changed the default to JSON in 1.6. If you upgrade
and switch from pickle to JSON, sessions created before the upgrade will be
lost. While JSON serialization does not support all Python objects like
-:mod:`pickle` does, we highly recommend using JSON-serialized sessions. See the
+:mod:`pickle` does, we highly recommend using JSON-serialized sessions. Also,
+as JSON requires string keys, you will likely run into problems if you are
+using non-string keys in ``request.session``. See the
:ref:`session_serialization` documentation for more details.
Miscellaneous
View
20 docs/topics/http/sessions.txt
@@ -325,7 +325,8 @@ Session serialization
Before version 1.6, Django defaulted to using :mod:`pickle` to serialize
session data before storing it in the backend. If you're using the :ref:`signed
cookie session backend<cookie-session-backend>` and :setting:`SECRET_KEY` is
-known by an attacker, the attacker could insert a string into his session
+known by an attacker (there isn't an inherent vulnerability in Django that
+would cause it to leak), the attacker could insert a string into his session
which, when unpickled, executes arbitrary code on the server. The technique for
doing so is simple and easily available on the internet. Although the cookie
session storage signs the cookie-stored data to prevent tampering, a
@@ -349,8 +350,21 @@ Bundled Serializers
.. class:: serializers.JSONSerializer
A wrapper around the JSON serializer from :mod:`django.core.signing`. Can
- only serialize basic data types. See the :ref:`custom-serializers` section
- for more details.
+ only serialize basic data types.
+
+ In addition, as JSON supports only string keys, note that using non-string
+ keys in ``request.session`` won't work as expected::
+
+ >>> # initial assignment
+ >>> request.session[0] = 'bar'
+ >>> # subsequent requests following serialization & deserialization
+ >>> # of session data
+ >>> request.session[0] # KeyError
+ >>> request.session['0']
+ 'bar'
+
+ See the :ref:`custom-serializers` section for more details on limitations
+ of JSON serialization.
.. class:: serializers.PickleSerializer

0 comments on commit c0fb6bd

Please sign in to comment.
Something went wrong with that request. Please try again.