Summary
=======

Bugzilla is a Web-based bug-tracking system, used by a large number of
software projects.

This advisory covers two security bugs that have recently been
discovered and fixed in the Bugzilla code:

 + Any user can change a flag on any bug. This also allows the 
   attacker to expose the summary of any bug, even a hidden bug.

 + Summaries of private bugs are sometimes exposed under a very rare
   condition if you use MySQL replication.

All Bugzilla installations are advised to upgrade to the latest stable
version of Bugzilla, 2.18.2.

Development snapshots of 2.19 and above are also vulnerable. If you are
using a development snapshot, you should upgrade to the release candidate
(2.20rc1), use CVS to update, or apply the patches from the specific 
bugs listed below.


Vulnerability Details
=====================

Issue 1
-------
Class:       Unauthorized Bug Change, Information Leak
Versions:    2.17.1 - 2.18.1, 2.19.1 - 2.19.3
Description: Any user can change any flag on any bug, even if they don't
             have access to that bug, or even if they can't normally
             make bug changes. This also allows them to expose the
             summary of a bug.
             By manually modifying a link to process_bug.cgi, it is possible
             to change a flag on a bug that you do not have access to,
             because Bugzilla does not validate that the flag you are 
             attempting to change is associated with the bug that you 
             are attempting to change.
             If the attacker makes a flag change which causes the attacker
             to be emailed, the attacker will see the summary of the bug
             in that email.
             If you are using the request_group or grant_group features
             of 2.19, the attacker will be prevented from exploiting
             this security hole if they do not have permission to
             change the flag in the fashion that they are changing it.
Reference:   https://bugzilla.mozilla.org/show_bug.cgi?id=293159

Issue 2
-------
Class:       Information Leak
Versions:    2.17.1 and above
Description: Bugs are inserted into the database before they are marked
             as private, in Bugzilla code. Thus, MySQL replication can
             lag in between the time that the bug is inserted and when
             it is marked as private (usually less than a second). If
             replication lags at this point, the bug summary will be 
             accessible to all users until replication catches up.
             Also, on a very slow machine, there may be a pause
             longer than a second that allows users to see the title of
             the newly-filed bug.
Reference:   https://bugzilla.mozilla.org/show_bug.cgi?id=292544


Vulnerability Solutions
=======================

The fixes for all of the security bugs mentioned in this advisory
are included in the 2.18.2 and 2.20rc1 releases.  Upgrading
to these releases will protect installations from possible exploits
of these issues.

Full release downloads, patches to upgrade Bugzilla from previous
versions, and CVS upgrade instructions are available at:
  https://www.bugzilla.org/download.html

Specific patches for each of the individual issues can be found on the
corresponding bug reports for each issue, at the URL given in the
reference for that issue in the list above.


Credits
=======

The Bugzilla team wish to thank the following people for their
assistance in locating, advising us of, and assisting us to fix 
these situations:

Frédéric Buclin
Matthias Versen
Joel Peshkin
Myk Melez

General information about the Bugzilla bug-tracking system can be found
at https://www.bugzilla.org/

Comments and follow-ups can be directed to the
netscape.public.mozilla.webtools newsgroup or the mozilla-webtools
mailing list; https://www.bugzilla.org/support/ has directions for
accessing these forums.