Vulnerability Note VU#120760

Yahoo! Installer Plugin for Widgets ActiveX control stack buffer overflow

Overview

The Yahoo! Installer Plugin for Widgets ActiveX control contains a stack buffer overflow, which can allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable system.

I. Description

Yahoo! Widgets is a program for Windows that allows the user to run applications called "widgets." Yahoo! Widgets includes an ActiveX control called Yahoo! Installer Plugin for Widgets. This ActiveX control, which is provided by YDPCTL.dll, contains a stack buffer overflow in the GetComponentVersion() method.

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

Apply an update

This issue is addressed in the July 24, 2007 Widgets Security Updates.

Disable the Yahoo! Installer Plugin for Widgets ActiveX control in Internet Explorer

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

{7EC7B6C5-25BD-4586-A641-D2ACBB6629DD}

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{7EC7B6C5-25BD-4586-A641-D2ACBB6629DD}]
"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
Yahoo, Inc.	Vulnerable	17-Aug-2007

References

http://www.cert.org/tech_tips/securing_browser/#Internet_Explorer
http://help.yahoo.com/l/us/yahoo/widgets/security/security-08.html
http://securitytracker.com/alerts/2007/Jul/1018470.html
http://www.securityfocus.com/bid/25086
http://secunia.com/advisories/26011/

Credit

This vulnerability was reported by Parvez Anwar.

This document was written by Will Dormann.

Other Information

Date Public	07/27/2007
Date First Published	08/17/2007 04:38:45 PM
Date Last Updated	08/21/2007
CERT Advisory
CVE Name	CVE-2007-4034
Metric	30.12
Document Revision	4