Vulnerability Note VU#599657

IBM and Lenovo Access Support acpRunner ActiveX control format string vulnerability

Overview

The IBM Lenovo Access Support acpRunner ActiveX control contains a format string vulnerability, which may allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable system.

I. Description

The Access Support software package for IBM and Lenovo systems includes several ActiveX controls. This software package is also known as Automated Solutions. The acpRunner control, which is provided by AcpController.dll, provides several methods that can be used to download, extract, and run software from a remote server. The acpRunner ActiveX control contains a format string vulnerability.

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. The attacker could also cause the web browser to crash.

III. Solution

Apply an update

This issue is addressed in Automated Solutions fix pack 1. This update removes the vulnerable control and also provides an updated version of the acpRunner ActiveX control that addresses the format string vulnerability.

This control also has been disabled via the kill bit in Microsoft Security Bulletin MS07-045.

Disable the acpRunner ActiveX control in Internet Explorer

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

{E598AC61-4C6F-4F4D-877F-FAC49CA91FA3}

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{E598AC61-4C6F-4F4D-877F-FAC49CA91FA3}]
"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 Updated
IBM Corporation	Vulnerable	25-Apr-2007
Lenovo	Vulnerable	14-Aug-2007

References

http://www.cert.org/tech_tips/securing_browser/#Internet_Explorer
http://www-307.ibm.com/pc/support/site.wss/document.do?sitestyle=lenovo&lndocid=MIGR-67649
http://www.microsoft.com/technet/security/Bulletin/MS07-045.mspx
http://support.microsoft.com/kb/240797

Credit

This vulnerability was reported by Will Dormann of CERT/CC.

This document was written by Will Dormann.

Other Information

Date Public	08/14/2007
Date First Published	08/14/2007 01:49:49 PM
Date Last Updated	08/14/2007
CERT Advisory
CVE Name	CVE-2007-2928
Metric	1.20
Document Revision	8