Immunity Debugger 1.85 - Crash PoC

ID EDB-ID:37526
Type exploitdb
Reporter Arsyntex
Modified 2015-07-08T00:00:00


Immunity Debugger 1.85 - Crash PoC. Dos exploit for windows platform

                                            # Title: Immunity Debugger - Crash
# Date: 08/07/2015
# Author: Arsyntex
# Vendor Homepage:
# Version: v1.85
# Tested on: Windows 8.1 Pro

Incorrect path/file EXtEnsion parsing.

-Create folder with the name: .exe.exe and put any program inside and try debug it.
-Try to debug an executable with the name: test.exe.exe or lib.exe.dll

The "OpenEXEfile" function does not check if the return value of strchr() is zero.

      mov     [esp+10h+var_10], edi
      add     edi, 4
      mov     [esp+10h+var_C], 20h
      mov     [esp+10h+arg_24], eax
      call    strchr                 ; return EAX=3D 0
      mov     [esp+10h+var_10], eax
      mov     [esp+10h+arg_28], eax  ; (!)
      call    strlen                 ; ntdll.strlen(s)

ntdll.strlen(s) - NULL parameter

      mov     ecx, [esp+4]           ; [esp+4] =3D 0  NULL pointer
      test    ecx, 3                 ; ...
      jz      short loc_77C77510     ; jump


      mov     eax, [ecx]             ; Access Violation