Public Vulnerability Reports

Apple iTunes Playlist Parsing Buffer Overflow Vulnerability

01.13.05

BACKGROUND

Apple iTunes is a digital jukebox capable of playing a variety of sound
file formats, sharing music and burning music CD's. More information
about iTunes is available from:

    http://www.apple.com/itunes/

DESCRIPTION

Remote exploitation of a buffer overflow vulnerability in Apple Computer
Inc.'s iTunes music player allows attackers to execute arbitrary code.

The problem specifically exists when parsing playlist files that contain
long URL file entries. Malicious playlist files can come with either the
.m3u or .pls extension. Though their formats are different, the
vulnerability in each is the same.

An example malicious .pls file with a long URL:

    [playlist]
    NumberOfEntries=1
    File1=http://[A x 3045]1234

An example malicious .m3u file with a long URL:

    http://[A x 3045]1234

In both cases '[A x 3045]' represents any string of 3,045 bytes in
length. Opening either malicious playlist file on the Microsoft Windows
platform will cause iTunes to crash with an access violation when
attempting to execute instruction 0x34333231, which is the little-endian
ASCII code representation of '1234'. An attacker can exploit this
vulnerability to redirect the flow of control and eventually execute
arbitrary code. While this example is specific to the Microsoft Windows
platform, exploitation on the Apple Mac OS platform is also possible.

ANALYSIS

Exploitation of the described vulnerability allows remote attackers to
execute arbitrary code under the context of the user who started iTunes.
Exploitation requires that an attacker convince a target user to open a
malicious playlist file with a vulnerable version of iTunes.

DETECTION

iTunes 4.7 as installed on the Microsoft Windows and Apple Mac OS
platforms are affected. Earlier versions may also be susceptible.

WORKAROUND

Do not open playlist files from untrusted sources. Inspect the contents
of .m3u and .pls playlist files for long URL file names prior to opening
them with iTunes.

VENDOR RESPONSE

This vulnerability is addressed in iTunes 4.7.1.

iTunes 4.7.1 may be obtained from the Software Update pane in System
Preferences, or Apple's iTunes download site:

   http://www.apple.com/itunes/download/

CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
names CAN-2005-0043 to these issues. This is a candidate for inclusion
in the CVE list (http://cve.mitre.org), which standardizes names for
security problems.

DISCLOSURE TIMELINE

12/17/2004   Initial vendor notification
12/17/2004   Initial vendor response
01/13/2004   Public disclosure

CREDIT

Sean de Regge (seanderegge[at]hotmail.com) is credited with this
discovery.

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LEGAL NOTICES

Copyright © 2004 Verisign, Inc.

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at the time of publishing based on currently available information. Use
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