search menu icon-carat-right cmu-wordmark

CERT Coordination Center

WinAmp contains a flaw in metadata handling in .mpa and .mp4 files

Vulnerability Note VU#372968

Original Release Date: 2005-02-21 | Last Revised: 2005-02-21


WinAmp contains a flaw which may allow an attacker to crash WinAmp remotely via .mpa or .mp4 files.


Nullsoft's WinAmp Player, a popular multimedia system for Microsoft Windows, contains a flaw in the handling of the metadata (called "tags") contained within .mpa and .mp4 files. Invalid data within these files could crash WinAmp.

WinAmp is susceptible to a remote Denial of Service flaw if maliciously crafted .mp4 or .mpa files are loaded. This flaw could cause WinAmp to unexpectedly crash. Also, the flaw may be exploited in combination with the default setting for some web browsers to automatically open WinAmp playlist (.pls, .m3u) files without prompting. A malicious playlist, with pointers to remote files on the Internet, may be embedded in a web page specifically crafted to automatically load the playlist. As such, a user may unintentionally load a flawed mpa or .mp4 file by following an innocuous web link.


WinAmp may crash, resulting in a denial of service to the user running it.


Apply an update

This flaw has been corrected in WinAmp version 5.08c and later. Download and install the latest version from:



Do not open .mpa, .mp4, .pls or .m3u files automatically with WinAmp in your web browser.
Do not open unknown .mpa, .mp4, .pls or .m3u files.

Of course, these recommendations always apply to any unknown files and file types. It is also always advised for all users to ensure their browser will prompt for the desired action (Save, Cancel, Open) with all filetypes that may load remote data, such as WinAmp .pls or .m3u playlist file types.

Vendor Information


Nullsoft Affected

Notified:  January 13, 2005 Updated: February 21, 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.


Updates which address this flaw may be found at the Nullsoft WinAmp web page.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

CVSS Metrics

Group Score Vector



This document was written by Ken MacInnis.

Other Information

CVE IDs: None
Severity Metric: 2.03
Date Public: 2004-12-22
Date First Published: 2005-02-21
Date Last Updated: 2005-02-21 21:21 UTC
Document Revision: 21

Sponsored by CISA.