Vulnerability Note VU#831457

RealNetworks RealPlayer ActiveX controls property heap memory corruption

Overview

Multiple RealPlayer ActiveX controls fail to properly handle properties, which can allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable system.

I. Description

RealNetworks RealPlayer provides multiple ActiveX controls to allow integration with Internet Explorer. The ActiveX controls provided by the file rmoc3260.dll fail to properly handle multiple properties, including Console. Setting these properties can result in heap memory corruption.

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 appears to be partially addressed in RealPlayer 11.0.2. This update provides version 6.0.10.50 of rmoc3260.dll. Please also consider the following workarounds:

Disable the RealPlayer ActiveX controls in Internet Explorer

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

{0FDF6D6B-D672-463B-846E-C6FF49109662}
{224E833B-2CC6-42D9-AE39-90B6A38A4FA2}
{2F542A2E-EDC9-4BF7-8CB1-87C9919F7F93}
{3B46067C-FD87-49B6-8DDD-12F0D687035F}
{3B5E0503-DE28-4BE8-919C-76E0E894A3C2}
{44CCBCEB-BA7E-4C99-A078-9F683832D493}
{A1A41E11-91DB-4461-95CD-0C02327FD934}
{CFCDAA03-8BE4-11CF-B84B-0020AFBBCCFA}

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 these controls:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{0FDF6D6B-D672-463B-846E-C6FF49109662}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{224E833B-2CC6-42D9-AE39-90B6A38A4FA2}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{2F542A2E-EDC9-4BF7-8CB1-87C9919F7F93}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{3B46067C-FD87-49B6-8DDD-12F0D687035F}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{3B5E0503-DE28-4BE8-919C-76E0E894A3C2}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{44CCBCEB-BA7E-4C99-A078-9F683832D493}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{A1A41E11-91DB-4461-95CD-0C02327FD934}]
"Compatibility Flags"=dword:00000400

[HKEY_LOCAL_MACHINESOFTWAREMicrosoftInternet ExplorerActiveX Compatibility{CFCDAA03-8BE4-11CF-B84B-0020AFBBCCFA}]
"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
RealNetworks, Inc.	Vulnerable	11-Mar-2008

References

http://secunia.com/advisories/29315/
http://archives.neohapsis.com/archives/fulldisclosure/2008-03/0157.html
http://isc.sans.org/diary.html?storyid=4120
http://lists.grok.org.uk/pipermail/full-disclosure/2008-March/060659.html

Credit

This vulnerability was publicly disclosed by Elazar Broad.

This document was written by Will Dormann.

Other Information

Date Public	03/10/2008
Date First Published	03/11/2008 01:55:45 PM
Date Last Updated	04/15/2008
CERT Advisory
CVE Name	CVE-2008-1309
US-CERT Technical Alerts
Metric	17.15
Document Revision	10