(This is not an official Mozilla advisory. My goal here is to bring
awareness about these issues to the users of Mozilla-based products, and
to provide some links to more detailed technical information about the
security bugs I found.)


Overview
--------

Firefox Preview Release, Thunderbird 0.8, and Mozilla 1.7.3 are
available for download at www.mozilla.org since Sept 13 and 14. These
releases fix 7 critical security issues, detailed on the "Known
Vulnerabilities in Mozilla" page:
http://www.mozilla.org/projects/security/known-vulnerabilities.html

Three of these issues are rated at maximum level "Severity: Critical"
and "Risk: High":

* Non-ascii hostname heap overrun (reported by Mats Palmgren, Gaël
  Delalleau)
   A link with a non-ascii hostname can cause a heap buffer overrun that
   could potentially be exploited to run arbitrary code.

* BMP integer overflow (reported by Gaël Delalleau)
   Extremely wide BMP images trigger an integer overflow, leading to
   heap overruns that are potentially exploitable to run arbitrary code.

* Buffer overflow when displaying VCard (reported by Georgi Guninski)
   A stack buffer overrun in VCard display routines could be exploited
   to run arbitrary code supplied by the attacker.


Technical information about the security bugs I reported
--------------------------------------------------------

These are some links to my original source code audit reports. I audited
parts of the Mozilla 1.7.2 C++ source code tree during my free time, in
an attempt to promote and participate to the Mozilla Security Bug Bounty
Program.

* Arbitrary code execution while parsing a malformed .BMP image
http://www.zencomsec.com/advisories/mozilla-1.7.2-BMP.txt

* Out of bounds writes in the POP3 protocol handler allows for arbitrary
code execution
http://www.zencomsec.com/advisories/mozilla-1.7.2-POP3.txt

* Non-ascii hostname heap overrun
http://www.zencomsec.com/advisories/mozilla-1.7.2-UTF8link.txt



Other products at risk?
-----------------------

Although not 100% verified, it is very likely some of these critical
security bugs are also exploitable in other products based on Mozilla,
like Netscape 7 and Galeon.

Users of such products should ask vendors for a patch, and meanwhile
apply the workarounds described on the "Known Vulnerabilities in
Mozilla" page.



Gaël Delalleau

Zencom Secure Solutions 
71 avenue d'Italie
75013 PARIS - FRANCE