Red Hat Security Advisory 2014-0008-01 - Ruby on Rails is a model-view-controller framework for web application development. Action Pack implements the controller and the view components. A flaw was found in the way Ruby on Rails performed JSON parameter parsing. An application using a third party library, which uses the Rack::Request interface, or custom Rack middleware could bypass the protection implemented to fix the CVE-2013-0155 vulnerability, causing the application to receive unsafe parameters and become vulnerable to CVE-2013-0155.
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