The Active Record component in Ruby on Rails before 3.0.14, 3.1.x before 3.1.6, and 3.2.x before 3.2.6 does not properly implement the passing of request data to a where method in an ActiveRecord class, which allows remote attackers to conduct certain SQL injection attacks via nested query parameters that leverage improper handling of nested hashes, a related issue to CVE-2012-2661.
The example code for the digest authentication functionality (http_authentication.rb) in Ruby on Rails before 2.3.3 defines an authenticate_or_request_with_http_digest block that returns nil instead of false when the user does not exist, which allows context-dependent attackers to bypass authentication for applications that are derived from this example by sending an invalid username without a password.