actionpack/lib/actiondispatch/http/request.rb in Ruby on Rails before 3.2.16 and 4.x before 4.0.2 does not properly consider differences in parameter handling between the Active Record component and the JSON implementation, which allows remote attackers to bypass intended database-query restrictions and perform NULL checks or trigger missing WHERE clauses via a crafted request that leverages (1) third-party Rack middleware or (2) custom Rack middleware. NOTE: this vulnerability exists because of an incomplete fix for CVE-2013-0155.

actionpack/lib/actionview/template/text.rb in Action View in Ruby on Rails 3.x before 3.2.17 converts MIME type strings to symbols during use of the :text option to the render method, which allows remote attackers to cause a denial of service (memory consumption) by including these strings in headers.

actionpack/lib/actionview/lookupcontext.rb in Action View in Ruby on Rails 3.x before 3.2.16 and 4.x before 4.0.2 allows remote attackers to cause a denial of service (memory consumption) via a header containing an invalid MIME type that leads to excessive caching.

Multiple cross-site scripting (XSS) vulnerabilities in actionview/lib/actionview/helpers/numberhelper.rb in Ruby on Rails before 3.2.17, 4.0.x before 4.0.3, and 4.1.x before 4.1.0.beta2 allow remote attackers to inject arbitrary web script or HTML via the (1) format, (2) negativeformat, or (3) units parameter to the (a) numbertocurrency, (b) numbertopercentage, or (c) numbertohuman helper.

Cross-site scripting (XSS) vulnerability in the numbertocurrency helper in actionpack/lib/actionview/helpers/numberhelper.rb in Ruby on Rails before 3.2.16 and 4.x before 4.0.2 allows remote attackers to inject arbitrary web script or HTML via the unit parameter.