05 Mar Security Advisory – SOS-10-002 – Apache 2.2.14 mod_isapi Dangling Pointer Vulnerability
Release Date: 05-Mar-2010
Last Update: –
Vendor Notification Date: 09-Feb-2010
Product: Apache HTTP Server
Platform: Microsoft Windows
Affected versions: 2.2.14 verified and possibly others
Severity Rating: High
Impact: Remote code execution with the privileges of the SYSTEM user
Attack Vector: Remote without authentication
Solution Status: Upgrade to 2.2.15 (as advised by Apache)
CVE reference: CVE – 2010-0425
The Apache HTTP Server, commonly referred to as Apache, is a popular open source web server software. mod_isapi is a core module of the Apache package that implements the Internet Server extension API. 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. This results in a dangling pointer vulnerability.
Successful exploitation results in the execution of arbitrary code with SYSTEM
Please refer to the PDF version of this advisory for proof of concept code examples.
Upgrade to the latest version of Apache HTTP Server (currently 2.2.15).
Brett Gervasoni from Sense of Security Labs.