Vulnerability Note VU#406937

PhotoStockPlus Uploader Tool ActiveX stack buffer overflows

Overview

The PhotoStockPlus Uploader Tool ActiveX control contains several stack buffer overflows, which may allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable system.

I. Description

PhotoStockPlus provides an image uploader ActiveX control, which is provided by the file PSPUploader.ocx. This ActiveX control contains stack buffer overflows in multiple initialization parameters, which can allow an overwrite of the process Structured Exception Handler (SEH).

PhotoStockPlus has indicated that the vulnerable ActiveX control is no longer used by the company. However, it is important to realize that any system that has used the control in the past may be at risk.

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 PhotoStockPlus Uploader Tool ActiveX control in Internet Explorer

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

{E48BB416-C578-4A62-84C9-5E3389ABE5FC}

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{E48BB416-C578-4A62-84C9-5E3389ABE5FC}]
"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
Photo Stock Plus . Com	Vulnerable	19-May-2008

References

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

Credit

This vulnerability was reported by Will Dormann of the CERT/CC.

This document was written by Will Dormann.

Other Information

Date Public	05/19/2008
Date First Published	05/19/2008 04:25:47 PM
Date Last Updated	06/19/2008
CERT Advisory
CVE Name	CVE-2008-0957
US-CERT Technical Alerts
Metric	1.70
Document Revision	7