Software Engineering Institute

The Acer LunchApp ActiveX control is provided by LunchApp.ocx. It contains a method called Run(), which takes three parameters: Drive, FileName, and CmdLine. Although the control is not inherently marked as safe for scripting via the IObjectSafety interface, it may be distributed with the appropriate Implemented Categories registry key to make it safe for scripting. This means that a web page in Internet Explorer can call the Run() method of the control.

By convincing a victim to view an HTML document (web page, HTML email, or email attachment), an attacker could run arbitrary commands with the privileges of the user running IE.

Apply an update

Acer has provided an update called Acer Preload Security Patch for Windows XP. This update unregisters and deletes the LunchApp.ocx file if it is present in the Windows System directory.

This vulnerability is also addressed by Microsoft Security Bulletin MS07-027. This update sets the kill bit for the vulnerable control.

Disable the Acer LunchApp ActiveX control in Internet Explorer

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

{D9998BD0-7957-11D2-8FED-00606730D3AA}
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\{D9998BD0-7957-11D2-8FED-00606730D3AA}]
"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.