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RealPlayer ActiveX control contains buffer overflow in "ShowPreferences"

Vulnerability Note VU#698390

Original Release Date: 2005-01-24 | Last Revised: 2005-01-27


The RealPlayer ActiveX control contains a stack-based buffer overflow in the ShowPreferences method. This may permit a remote attacker to execute arbitrary code on the user's system.


RealNetworks RealPlayer is a multimedia application that allows users to view local and remote audio/video content. The RealPlayer ActiveX control allows web authors to embed the RealPlayer application in HTML documents and have control over it. One of the exported functions of the RealPlayer ActiveX control is HandleAction, which executes a method or action. When the HandleAction function is used to call the ShowPreferences method, the RealPlayer preferences dialog is displayed, showing the specified category and page.

The ShowPreferences method concatenates its two arguments and then makes an unchecked call to sprintf(). By passing long arguments to ShowPreferences, an attacker can cause a stack-based buffer overflow to occur. Any browser that supports ActiveX may be affected, including IE and other software that uses MSHTML.


By convincing a user to view an HTML document (e.g., a web page or HTML email messsage), an attacker could execute arbitrary commands or code with the privileges of the user. The attacker could take any action as the user. If the user has administrative privileges, the attacker could take complete control of the user's system.


Install update
Install an update, as specified by the RealNetworks security advisory.

Disable Active scripting and ActiveX controls

To protect against this and other vulnerabilities in ActiveX controls, consider disabling Active scripting and ActiveX controls in the Internet Zone as described in the Malicious Web Scripts FAQ. Note that disabling Active scripting and ActiveX controls in the Internet Zone will reduce the functionality of some web sites.

Vendor Information


RealNetworks Affected

Updated:  January 24, 2005



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


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Thanks to NGSSoftware Insight Security Research for reporting this vulnerability.

This document was written by Will Dormann.

Other Information

CVE IDs: None
Severity Metric: 14.63
Date Public: 2004-09-28
Date First Published: 2005-01-24
Date Last Updated: 2005-01-27 18:49 UTC
Document Revision: 15

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