# MA-219.032010: MyCERT Alert - Apache mod_isapi Dangling Pointer Vulnerability

**Date:** 09 Mar 2010  
**Source:** https://www.mycert.org.my/portal/advisory?id=MA-219.032010  
**Advisory ID:** MA-219.032010

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**1.0 Introduction**
One of the core modules in Apache package that implements the Internet Server extension API is mod isapi. The extension allows Apache to serve Internet Server extensions (ISAPI .dll modules) for Microsoft Windows based hosts.
By sending a specially crafted request followed by a reset packet it is possible to trigger a vulnerability in Apache mod\_isapi that will unload the target ISAPI module from memory. However function pointers still remain in memory and are called when published ISAPI functions are referenced resulting dangling pointer vulnerability (CVE-2010-0425)
**2.0 Impact**
On Windows platforms using mod\_isapi, a remote attacker could send a malicious request to trigger this issue, and as win32 MPM runs only one process, this would result in a denial of service, and potentially allow arbitrary code execution.
**3.0 Affected Products**
Only Windows version of Apache software affected to this vulnerability. Below are the details of vulnerable versions:
- Apache Software Foundation Apache 2.2.14
- Apache Software Foundation Apache 2.2.13
- Apache Software Foundation Apache 2.2.12
- Apache Software Foundation Apache 2.2.11
- Apache Software Foundation Apache 2.2.10
- Apache Software Foundation Apache 2.2.9
- Apache Software Foundation Apache 2.2.8
- Apache Software Foundation Apache 2.2.6
- Apache Software Foundation Apache 2.2.5
- Apache Software Foundation Apache 2.2.4
- Apache Software Foundation Apache 2.2.3
- Apache Software Foundation Apache 2.2.2
- Apache Software Foundation Apache 2.2.0
- Apache Software Foundation Apache 2.2.7-dev
- Apache Software Foundation Apache 2.2.6-dev
- Apache Software Foundation Apache 2.2.5-dev
- Apache Software Foundation Apache 2.2.1
- Apache Software Foundation Apache 2.2
**4.0 Recommendation**
MyCERT recommends system administrator of this application to upgrade to version
2.2.15. The update can be obtained via this URL:
> <http://httpd.apache.org/download.cgi>
MyCERT advises users of this product to keep themselves updated with the latest security announcements by the vendor.
MyCERT can be reached through the following channels for further assistance:
E-mail : [[email protected]](/cdn-cgi/l/email-protection#365b4f55534442765b4f5553444218594451185b4f)
Phone : +603 89926969 or 1-300-88-2999 (monitored during business hours)
Fax : +603 89453442
Handphone : +60 19 2665850 (24x7 call incident reporting)
SMS : +60 19 2813801 (24x7 SMS reporting)
Business Hours : Mon - Fri 08:30 -17:30 MYT
Web: [https://www.mycert.org.my](https://www.mycert.org.my/) 
**5.0 References**
- <http://www.senseofsecurity.com.au/advisories/SOS-10-002>
- <http://httpd.apache.org/security/vulnerabilities_22.html>
- <http://www.securityfocus.com/bid/38494/>