CVE-2008-7248
Ruby on Rails 2.1 before 2.1.3 and 2.2.x before 2.2.2 does not verify tokens for requests with certain content types, which allows remote attackers to bypass cross-site request forgery (CSRF) protection for requests to applications that rely on this protection, as demonstrated using text/plain.
Date published : 2009-12-15
http://weblog.rubyonrails.org/2008/11/18/potential-circumvention-of-csrf-protection-in-rails-2-1
http://groups.google.com/group/rubyonrails-security/browse_thread/thread/d741ee286e36e301?hl=en