Software Engineering Institute

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.

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.

Apply an update
This ActiveX control has been disabled in Internet Explorer with the update for Microsoft Security Advisory (956391).

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_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX 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.