Ticket #30875: plugin.patch

wp-includes/plugin.php

@@ -81 +81 @@
 function add_filter( $tag, $function_to_add, $priority = 10, $accepted_args = 1 ) {
         global $wp_filter, $merged_filters;
 
+        if( !is_int($priority) )
+                return false;
+
         $idx = _wp_filter_build_unique_id($tag, $function_to_add, $priority);
         $wp_filter[$tag][$priority][$idx] = array('function' => $function_to_add, 'accepted_args' => $accepted_args);
         unset( $merged_filters[ $tag ] );