Directory traversal vulnerability in includes/search/search_mdforum.php in MAXdev MDForum 2.0.1 and earlier, when magic_quotes_gpc is disabled and register_globals is enabled, allows remote attackers to include and execute arbitrary local files via a .. (dot dot) in the PNSVlang cookie to error.php, as demonstrated by injecting PHP sequences into an Apache HTTP Server log file, which is then included by error.php.