Ticket #17814: 17814.patch

wp-includes/media.php

@@ -247 +247 @@
         if ( is_numeric( $file ) )
                 $file = get_attached_file( $file );
 
-        if ( ! file_exists( $file ) )
+        if ( ! file_exists( $file ) || ! is_file( $file ) )
                 return sprintf(__('File “%s” doesn’t exist?'), $file);
 
         if ( ! function_exists('imagecreatefromstring') )