Vulnerability Note VU#194505

Symantec AppStream LaunchObj ActiveX control vulnerable to arbitrary code download and execution

Overview

The Symantec AppStream LaunchObj ActiveX control contains methods that can be used to download and execute arbitrary code.

I. Description

Symantec AppStream is an application deployment framework for Microsoft Windows. One of the components of the AppStream Windows Client is an ActiveX control that is provided by launcher.dll. This ActiveX control is marked Safe for Scripting in Internet Explorer and contains a number of unsafe methods, such as installAppMgr(), which can be used to download and execute arbitrary code.

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

Apply an update

This issue is resolved in the Symantec AppStream Client 5.2.2 SP3 MP1. This version of the client software provides version 5.2.2.865 of the LaunchObj ActiveX control, which performs additional validation of downloaded files. Please see Symantec Advisory SYM09-001 for more details.

Disable the LaunchObj ActiveX control in Internet Explorer

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

{3356DB7C-58A7-11D4-AA5C-006097314BF8}

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{3356DB7C-58A7-11D4-AA5C-006097314BF8}]
"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 Notified	Date Updated
Symantec, Inc.	Vulnerable	2008-10-17	2009-01-15

References

http://www.cert.org/tech_tips/securing_browser/
http://www.symantec.com/avcenter/security/Content/2009.01.15.html
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:	2009-01-15
Date First Published:	2009-01-15
Date Last Updated:	2009-01-15
CERT Advisory:
CVE-ID(s):	CVE-2008-4388
NVD-ID(s):	CVE-2008-4388
US-CERT Technical Alerts:
Metric:	5.68
Document Revision:	8