Cross-site scripting (XSS) vulnerability in Action View in Ruby on Rails 3.x before 3.2.22.3, 4.x before 4.2.7.1, and 5.x before 5.0.0.1 might allow remote attackers to inject arbitrary web script or HTML via text declared as "HTML safe" and used as attribute values in tag handlers.

Action Record in Ruby on Rails 4.2.x before 4.2.7.1 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, as demonstrated by certain "[nil]" values, a related issue to CVE-2012-2660, CVE-2012-2694, and CVE-2013-0155.

Action Pack in Ruby on Rails before 3.2.22.2, 4.x before 4.1.14.2, and 4.2.x before 4.2.5.2 allows remote attackers to execute arbitrary Ruby code by leveraging an application's unrestricted use of the render method.

The http_basic_authenticate_with method in actionpack/lib/action_controller/metal/http_authentication.rb in the Basic Authentication implementation in Action Controller in Ruby on Rails before 3.2.22.1, 4.0.x and 4.1.x before 4.1.14.1, 4.2.x before 4.2.5.1, and 5.x before 5.0.0.beta1.1 does not use a constant-time algorithm for verifying credentials, which makes it easier for remote attackers to bypass authentication by measuring timing differences.

actionpack/lib/action_dispatch/routing/route_set.rb in Action Pack in Ruby on Rails 4.x before 4.2.5.1 and 5.x before 5.0.0.beta1.1 allows remote attackers to cause a denial of service (superfluous caching and memory consumption) by leveraging an application's use of a wildcard controller route.

activerecord/lib/active_record/nested_attributes.rb in Active Record in Ruby on Rails 3.1.x and 3.2.x before 3.2.22.1, 4.0.x and 4.1.x before 4.1.14.1, 4.2.x before 4.2.5.1, and 5.x before 5.0.0.beta1.1 does not properly implement a certain destroy option, which allows remote attackers to bypass intended change restrictions by leveraging use of the nested attributes feature.

actionpack/lib/action_dispatch/http/mime_type.rb in Action Pack in Ruby on Rails before 3.2.22.1, 4.0.x and 4.1.x before 4.1.14.1, 4.2.x before 4.2.5.1, and 5.x before 5.0.0.beta1.1 does not properly restrict use of the MIME type cache, which allows remote attackers to cause a denial of service (memory consumption) via a crafted HTTP Accept header.