Index: wp-admin/js/updates.js
===================================================================
--- wp-admin/js/updates.js	(revision 41035)
+++ wp-admin/js/updates.js	(working copy)
@@ -1997,6 +1997,7 @@
 		 * @param {Event} event Event interface.
 		 */
 		$bulkActionForm.on( 'click', '[type="submit"]', function( event ) {
+
 			var bulkAction    = $( event.target ).siblings( 'select' ).val(),
 				itemsSelected = $bulkActionForm.find( 'input[name="checked[]"]:checked' ),
 				success       = 0,
@@ -2004,6 +2005,10 @@
 				errorMessages = [],
 				type, action;
 
+            if ( bulkAction == 'update-selected' && $('.updating-message')[0] ) {
+                return false;
+            }
+
 			// Determine which type of item we're dealing with.
 			switch ( pagenow ) {
 				case 'plugins':