Vulnerability Note VU#889484

libpng off-by-one vulnerability

Original Release date: 02 Oct 2008 | Last revised: 02 Oct 2008

Overview

A vulnerability exists in libpng that may allow a remote attacker to cause a denial of service.

Description

A vulnerability in the way libpng handles files that contain multiple zTXt chunks may cause a denial of service. This vulnerability is due to an off-by-one error introduced in the png_push_read_zTXt() function in libpng-1.2.30/pngpread.c. According to the PNG Development Group:

    Gecko-based applications such as Firefox are not vulnerable because they contain a png_set_keep_unknown_chunks() call that causes the application to ignore the zTXt chunk.


Note that this issue affects libpng versions 1.0.38, 1.0.39, 1.2.30, 1.2.31, and libpng-1.4.0beta.

Impact

A remote, unauthorized attacker may be able to cause a denial of service.

Solution

Upgrade
The PNG Development Group has issued an upgrade to address this issue. See libpng version 1.2.32 for more information.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
libpngAffected-02 Oct 2008
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A N/A

References

Credit

This issue was reported by the PNG Development Group in libpng version 1.2.32.

This document was written by Chris Taschner.

Other Information

  • CVE IDs: CVE-2008-3964
  • Date Public: 05 Sep 2008
  • Date First Published: 02 Oct 2008
  • Date Last Updated: 02 Oct 2008
  • Severity Metric: 3.97
  • Document Revision: 7

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