Ticket #16702: 16702.3.patch

wp-includes/user.php

@@ -730 +730 @@
 function is_blog_user( $blog_id = 0 ) {
         global $wpdb;
 
-        $current_user = wp_get_current_user();
         if ( !$blog_id )
                 $blog_id = $wpdb->blogid;
 
-        $cap_key = $wpdb->base_prefix . $blog_id . '_capabilities';
+        $blogs = get_blogs_of_user( get_current_user_id() );
 
-        if ( is_array($current_user->$cap_key) && in_array(1, $current_user->$cap_key) )
-                return true;
-
-        return false;
+        return is_array( $blogs ) && array_key_exists( $blog_id, $blogs );
 }
 
 /**