Software Engineering Institute

The eBay Enhanced Picture Uploader ActiveX control is used by the eBay web site to give Internet Explorer users additional functionality when uploading pictures to an auction. This ActiveX control is provided by the file EPUWALcontrol.dll. If an attacker provides a specially-crafted PictureUrls property or initialization parameter, the ActiveX control will execute the commands that are specified.

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 commands with the privileges of the user.

Apply an update

This update is addressed in version 1.0.27 of the Ebay Enhanced Picture Control software. This update can be obtained by visiting the eBay web site, creating a new auction and uploading images with the Internet Explorer web browser. This control is also disabled in Internet Explorer with the update for Microsoft Security Advisory (969898). Please see the eBay security center announcement for additional details.

Please also consider the following workarounds:

Disable the eBay Enhanced Picture Uploader ActiveX control in Internet Explorer

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

{4C39376E-FA9D-4349-BACC-D305C1750EF3}
{C3EB1670-84E0-4EDA-B570-0B51AAE81679}
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\{4C39376E-FA9D-4349-BACC-D305C1750EF3}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ActiveX Compatibility\{C3EB1670-84E0-4EDA-B570-0B51AAE81679}]
"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.