diff --git a/vendor/assets/javascripts/jquery.js b/vendor/assets/javascripts/jquery.js
index 9b5206bcc6..fe7c3fc62e 100644
--- a/vendor/assets/javascripts/jquery.js
+++ b/vendor/assets/javascripts/jquery.js
@@ -261,8 +261,9 @@ jQuery.extend = jQuery.fn.extend = function() {
 				src = target[ name ];
 				copy = options[ name ];
 
+				// Prevent Object.prototype pollution
 				// Prevent never-ending loop
-				if ( target === copy ) {
+				if ( name === "__proto__" || target === copy  ) {
 					continue;
 				}