Ticket #20378: 20378.patch

wp-admin/includes/update.php

@@ -221 +221 @@
         $current = get_site_transient('update_themes');
         $update_themes = array();
 
-        foreach ( $current->response as $stylesheet => $data ) {
-                $update_themes[ $stylesheet ] = wp_get_theme( $stylesheet );
-                $update_themes[ $stylesheet ]->update = $data;
+        if ( isset( $current->response ) ) {
+                foreach ( $current->response as $stylesheet => $data ) {
+                        $update_themes[ $stylesheet ] = wp_get_theme( $stylesheet );
+                        $update_themes[ $stylesheet ]->update = $data;
+                }
         }
 
         return $update_themes;