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

Details

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
privileges.

Please refer to the PDF version of this advisory  for proof of concept code examples.

Solution

Upgrade to the latest version of Apache HTTP Server (currently 2.2.15).

Discovered By

Brett Gervasoni from Sense of Security Labs.