Software Engineering Institute

The Symantec Automated Support Assistant control is an ActiveX control that comes with several Symantec products, including Norton AntiVirus, Norton Internet Security, and Norton System Works. The Automated Support Assistant ActiveX control contains a buffer overflow vulnerability.

Note that the vulnerable ActiveX control is locked to the symantec.com domain. This means that a web page that is not in the symantec.com domain cannot call the vulnerable methods. Therefore, an attacker would need to also subvert the host name lookup methodology on a victim's system to exploit this buffer overflow vulnerability.

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. The attacker could also cause Internet Explorer (or the program using the WebBrowser control) to crash.

Apply an update
According to Symantec Advisory SYM06-019:

Symantec product engineers have developed and released solutions for this issue through Symantec's LiveUpdate and other venues.

Symantec users who normally run regular manual LiveUpdates will already be protected. However, to ensure all available patches have been properly applied to Symantec products, users should run a manual LiveUpdate as follows:

   * Open any installed Symantec consumer product identified above
   * Click on LiveUpdate in the toolbar
   * Run LiveUpdate until all available Symantec product updates are downloaded and installed

Symantec product engineers have upgraded the current vulnerable component on the Symantec support website so users will be able to download a non-vulnerable version of the Automated Support Assistant.

Disable the Symantec Automated Support Assistant ActiveX control in Internet Explorer

The Symantec Automated Support Assistant ActiveX control can be disabled in Internet Explorer by setting the kill bit for the following CLSID:

{CE28D5D2-60CF-4C7D-9FE8-0F47A3308078}
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\{CE28D5D2-60CF-4C7D-9FE8-0F47A3308078}]
"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.