Ember.js 1.0.x before 1.0.1 1.1.x before 1.1.3 1.2.x before 1.2.1 1.3.x before 1.3.1 and 1.4.x before 1.4.0-beta.2 allows remote attackers to conduct cross-site scripting (XSS) attacks by leveraging an application using the \{{group}}\ Helper and a crafted payload.