The Active Record component in Ruby on Rails 2.3.x before 2.3.18, 3.1.x before 3.1.12, and 3.2.x before 3.2.13 processes certain queries by converting hash keys to symbols, which allows remote attackers to cause a denial of service via crafted input to a where method.
The sanitize_css method in lib/action_controller/vendor/html-scanner/html/sanitizer.rb in the Action Pack component in Ruby on Rails before 2.3.18, 3.0.x and 3.1.x before 3.1.12, and 3.2.x before 3.2.13 does not properly handle \n (newline) characters, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via crafted Cascading Style Sheets (CSS) token sequences.
The ActiveSupport::XmlMini_JDOM backend in lib/active_support/xml_mini/jdom.rb in the Active Support component in Ruby on Rails 3.0.x and 3.1.x before 3.1.12 and 3.2.x before 3.2.13, when JRuby is used, does not properly restrict the capabilities of the XML parser, which allows remote attackers to read arbitrary files or cause a denial of service (resource consumption) via vectors involving (1) an external DTD or (2) an external entity declaration in conjunction with an entity reference.
The sanitize helper in lib/action_controller/vendor/html-scanner/html/sanitizer.rb in the Action Pack component in Ruby on Rails before 2.3.18, 3.0.x and 3.1.x before 3.1.12, and 3.2.x before 3.2.13 does not properly handle encoded : (colon) characters in URLs, which makes it easier for remote attackers to conduct cross-site scripting (XSS) attacks via a crafted scheme name, as demonstrated by including a : sequence.
ActiveRecord in Ruby on Rails before 2.3.17, 3.1.x before 3.1.11, and 3.2.x before 3.2.12 allows remote attackers to bypass the attr_protected protection mechanism and modify protected model attributes via a crafted request.