Vulnerability Note VU#661651

Mozilla Thunderbird external-body MIME type buffer overflow

Original Release date: 06 Mar 2008 | Last revised: 06 Mar 2008


Mozilla Thunderbird contains a heap-based buffer overflow which may allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable system.


Mozilla Thunderbird is an open source, cross-platform email and news client. Thunderbird uses Multipurpose Internet Message Extensions (MIME) which extends support in Thunderbird for multi-part message bodies, non-text attachments, and non-ASCII character sets. A vulnerability exists in the way Mozilla Thunderbird parses external-body MIME type in an electronic mail which may result in a heap-based buffer overflow. According to Mozilla Foundation Security Advisory 2008-12:

The vulnerability is caused by allocating a buffer that can be three bytes too small in certain cases when viewing an email message with an external MIME body.


A remote, unauthenticated attacker may be able to execute arbitrary code on a system running a vulnerable version of Mozilla Thunderbird.


Apply Update

Mozilla has has addressed this vulnerability in version For further information regarding this vulnerability, Mozilla has published MFSA-2008-12.

Apply Workaround

As stated directly from MFSA-2008-12:

Users can prevent the vulnerable code from being triggered by setting the "mailnews.display.disallow_mime_handlers" property to any value greater than or equal to 3.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
MozillaAffected-06 Mar 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



This vulnerability was reported to VeriSign iDefense by regenrecht.

This document was written by Joseph W. Pruszynski.

Other Information

  • CVE IDs: CVE-2008-0304
  • Date Public: 26 Feb 2008
  • Date First Published: 06 Mar 2008
  • Date Last Updated: 06 Mar 2008
  • Severity Metric: 31.00
  • Document Revision: 23


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