actionpack/lib/action_view/template/resolver.rb in Ruby on Rails 3.0.x before 3.0.4, when a case-insensitive filesystem is used, does not properly implement filters associated with the list of available templates, which allows remote attackers to bypass intended access restrictions via an action name that uses an unintended case for alphabetic characters.

References

• https://nvd.nist.gov/vuln/detail/CVE-2011-0449
• http://groups.google.com/group/rubyonrails-security/msg/04345b2e84df5b4f?dmode=source&output=gplain
• http://lists.fedoraproject.org/pipermail/package-announce/2011-April/057650.html
• http://weblog.rubyonrails.org/2011/2/8/new-releases-2-3-11-and-3-0-4
• rails/rails@6f80224
• https://github.com/rubysec/ruby-advisory-db/blob/master/gems/actionpack/CVE-2011-0449.yml
• https://web.archive.org/web/20201207190612/http://securitytracker.com/id?1025061