The internationalization (i18n) framework in Django 0.91, 0.95, 0.95.1, and 0.96, and as used in other products such as PyLucid, when the USE_I18N option and the i18n component are enabled, allows remote attackers to cause a denial of service (memory consumption) via many HTTP requests with large Accept-Language headers.

The LazyUser class in the AuthenticationMiddleware for Django 0.95 does not properly cache the user name across requests, which allows remote authenticated users to gain the privileges of a different user.

bin/compile-messages.py in Django 0.95 does not quote argument strings before invoking the msgfmt program through the os.system function, which allows attackers to execute arbitrary commands via shell metacharacters in a (1) .po or (2) .mo file.