iDefense Security Advisory 02.01.06: Winamp m3u/pls .WMA Extension Buffer Overflow Vulnerability

2006-02-02T00:00:00
ID SECURITYVULNS:DOC:11266
Type securityvulns
Reporter Securityvulns
Modified 2006-02-02T00:00:00

Description

Winamp m3u/pls .WMA Extension Buffer Overflow Vulnerability

iDefense Security Advisory 02.01.06 http://www.idefense.com/intelligence/vulnerabilities/display.php?id=378 February 1, 2006

I. BACKGROUND

Winamp is a popular media player for Windows which supports many audio/video file formats.

More information can be obtained from the vendors site at:

http://winamp.com/player/

II. DESCRIPTION

It has been found that a specially crafted m3u or pls file with a target filename having the .wma extension can crash Winamp giving the attacker control over the EAX register.

Example m3U file format:

EXTM3U

EXTINF:,VULN

AAAA[...]AA.wma

Example pls file format:

[playlist] numberofentries=5 File1=AAAA[...]AA.wma Title1= Length5=-1 Version=2

III. ANALYSIS

When Winamp is installed it registers the m3u and pls extensions so that such files will automatically open in Winamp. This exploit can be triggered by clicking on a link in a web page, or through the use of malicious javascript.

The crash occurs in the Winamp module with the following instructions:

mov edx, [eax] call [edx+24]

The number of characters that can be inject is limited. With control of the EAX register injected into the above code, meaningful shellcode execution is possible.

IV. DETECTION

This vulnerability has been verified in version 5.094 of Winamp.

V. WORKAROUND

Removing the file mapping for m3u and pls files to Winamp should mitigate the risk of exploitation.

VI. VENDOR RESPONSE

The vendor has not responded to communication regarding this vulnerability.

The vulnerability appears to have been silently fixed in Winamp 5.11. Version 5.13 is now available for download at:

http://www.winamp.com/player/

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the name CVE-2005-3188 to this issue. This is a candidate for inclusion in the CVE list (http://cve.mitre.org), which standardizes names for security problems.

VIII. DISCLOSURE TIMELINE

10/12/2005 Initial vendor notification 02/01/2006 Coordinated public disclosure

IX. CREDIT

This vulnerability was discovered by b0f.

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X. LEGAL NOTICES

Copyright (c) 2006 iDefense, Inc.

Permission is granted for the redistribution of this alert electronically. It may not be edited in any way without the express written consent of iDefense. If you wish to reprint the whole or any part of this alert in any other medium other than electronically, please email customerservice@idefense.com for permission.

Disclaimer: The information in the advisory is believed to be accurate at the time of publishing based on currently available information. Use of the information constitutes acceptance for use in an AS IS condition. There are no warranties with regard to this information. Neither the author nor the publisher accepts any liability for any direct, indirect, or consequential loss or damage arising from use of, or reliance on, this information.