Launchpad.net

CVE 2016-6316

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.

See the CVE page on Mitre.org for more details.