Vulnerability Note VU#172489

RealNetworks products fail to properly handle chunked data

RealNetworks RealPlayer is a multimedia application that allows users to view local and remote audio/video content.

Chunked Encoding

Chunked encoding is a means to transfer variable-sized units of data (called chunks) from a web client to a web server.

The Problem

Numerous RealNetworks products fail to properly handle file chunks allowing a buffer overflow to occur. By persuading a user to access a RealPlayer file hosted on a malicious server, a remote attacker may be able to execute arbitrary code.

Considerations

A complete list of affected software is available in the RealNetwork Security Update for March 2006.

II. Impact

Apply the patches supplied in the RealNetwork Security Update for March 2006.

Disable RealPlayer in your web browser

An attacker may be able to exploit this vulnerability by persuading a user to access a RealPlayer file with a web browser. Disabling RealPlayer in the web browser will eliminate this attack vector thereby reducing the chances of exploitation.

To disable RealPlayer in Microsoft Internet Explorer, disable the RealPlayer ActiveX control. In other web browsers, such as Mozilla Firefox, disable the RealPlayer plugin.

Systems Affected

http://www.idefense.com/intelligence/vulnerabilities/display.php?id=404
http://securitytracker.com/id?1015808
http://www.service.real.com/realplayer/security/03162006_player/en/
http://secunia.com/advisories/19358/
http://secunia.com/advisories/19365/

Credit

This vulnerability was reported by iDEFENSE Labs.

This document was written by Jeff Gennari.

Other Information

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