The PHP configuration directive allow_url_include is enabled. When enabled, this directive allows data retrieval from remote locations (web site or FTP server) for functions like fopen and file_get_contents. If user input is not properly validated, this can conduct to remote file inclusion vulnerabilities.
allow_url_include is disabled by default. If allow_url_fopen is disabled, allow_url_include is also disabled. This setting is only available since PHP 5.2.
You can disable allow_url_include from php.ini or .htaccess.
allow_url_include = 'off'
php_flag allow_url_include off