Index: wp-includes/css/media-views.css
===================================================================
--- wp-includes/css/media-views.css	(revision 22954)
+++ wp-includes/css/media-views.css	(working copy)
@@ -210,6 +210,7 @@
 	background: #f5f5f5;
 	border-left: 1px solid #dfdfdf;
 	overflow: auto;
+	-webkit-overflow-scrolling: touch;
 }
 
 .hide-toolbar .media-sidebar {
@@ -472,6 +473,7 @@
 .attachments {
 	margin: 0;
 	padding-right: 16px;
+	-webkit-overflow-scrolling: touch;
 }
 
 /**