Vulnerability Note VU#501843

Creative Software AutoUpdate Engine ActiveX stack buffer overflow

Overview

The Creative Labs AutoUpdate Engine ActiveX control contains a stack buffer overflow, which can allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable system.

I. Description

The Creative Software AutoUpdate Engine ActiveX control is a component that provides automatic update capabilities to Creative Labs software. This ActiveX control is provided by the file CTSUEng.ocx. The Create Software AutoUpdate Engine ActiveX control is marked Safe For Scripting and Safe For Initialization, which means that a web page in Internet Explorer has the ability to interact with the control. This ActiveX control contains a stack buffer overflow in the CacheFolder property.

Exploit code for this vulnerability is publicly available.

II. Impact

By convincing a user to view a specially crafted HTML document (e.g., a web page or an HTML email message or attachment), an attacker may be able to execute arbitrary code with the privileges of the user.

III. Solution

We are currently unaware of a practical solution to this problem. Please consider the following workarounds:

Disable the Creative Software AutoUpdate ActiveX control in Internet Explorer

The vulnerable ActiveX control can be disabled in Internet Explorer by setting the kill bit for the following CLSID:

{0A5FD7C5-A45C-49FC-ADB5-9952547D5715}

More information about how to set the kill bit is available in Microsoft Support Document 240797. Alternatively, the following text can be saved as a .REG file and imported to set the kill bit for this control:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{0A5FD7C5-A45C-49FC-ADB5-9952547D5715}]
"Compatibility Flags"=dword:00000400

Disable ActiveX

Disabling ActiveX controls in the Internet Zone (or any zone used by an attacker) appears to prevent exploitation of this and other ActiveX vulnerabilities. Instructions for disabling ActiveX in the Internet Zone can be found in the "Securing Your Web Browser" document.

Systems Affected

Vendor	Status	Date Updated
Creative Labs	Vulnerable	26-May-2008

References

http://www.cert.org/tech_tips/securing_browser/
http://support.microsoft.com/kb/240797

Credit

Thanks to Greg Linares of eEye Digital Security for reporting this vulnerability.

This document was written by Will Dormann.

Other Information

Date Public	05/27/2008
Date First Published	05/27/2008 11:04:12 AM
Date Last Updated	05/28/2008
CERT Advisory
CVE Name	CVE-2008-0955
US-CERT Technical Alerts
Metric	9.87
Document Revision	16