
Bugzilla Security
*****************

While some of the items in this chapter are related to the operating
system Bugzilla is running on or some of the support software required
to run Bugzilla, it is all related to protecting your data. This is
not intended to be a comprehensive guide to securing Linux, Apache,
MySQL, or any other piece of software mentioned. There is no
substitute for active administration and monitoring of a machine. The
key to good security is actually right in the middle of the word: *U R
It*.

While programmers in general always strive to write secure code,
accidents can and do happen. The best approach to security is to
always assume that the program you are working with isn't 100% secure
and restrict its access to other parts of your machine as much as
possible.


Operating System
================


TCP/IP Ports
------------

The TCP/IP standard defines more than 65,000 ports for sending and
receiving traffic. Of those, Bugzilla needs exactly one to operate
(different configurations and options may require up to 3). You should
audit your server and make sure that you aren't listening on any ports
you don't need to be. It's also highly recommended that the server
Bugzilla resides on, along with any other machines you administer, be
placed behind some kind of firewall.


System User Accounts
--------------------

Many daemons, such as Apache's "httpd" or MySQL's "mysqld", run as
either "root" or "nobody". This is even worse on Windows machines
where the majority of services run as "SYSTEM". While running as
"root" or "SYSTEM" introduces obvious security concerns, the problems
introduced by running everything as "nobody" may not be so obvious.
Basically, if you run every daemon as "nobody" and one of them gets
compromised it can compromise every other daemon running as "nobody"
on your machine. For this reason, it is recommended that you create a
user account for each daemon.

Note: You will need to set the "webservergroup" option in "localconfig" to
  the group your web server runs as. This will allow "./checksetup.pl"
  to set file permissions on Unix systems so that nothing is world-
  writable.


The "chroot" Jail
-----------------

If your system supports it, you may wish to consider running Bugzilla
inside of a "chroot" jail. This option provides unprecedented security
by restricting anything running inside the jail from accessing any
information outside of it. If you wish to use this option, please
consult the documentation that came with your system.


Web server
==========


Disabling Remote Access to Bugzilla Configuration Files
-------------------------------------------------------

There are many files that are placed in the Bugzilla directory area
that should not be accessible from the web server. Because of the way
Bugzilla is currently layed out, the list of what should and should
not be accessible is rather complicated. A quick way is to run
"testserver.pl" to check if your web server serves Bugzilla files as
expected. If not, you may want to follow the few steps below.

Note: Bugzilla ships with the ability to create ".htaccess" files that
  enforce these rules. Instructions for enabling these directives in
  Apache can be found in *Bugzilla using Apache*

* In the main Bugzilla directory, you should: - Block: "*.pl",
  "*localconfig*"

* In "data": - Block everything

* In "data/webdot":

  * If you use a remote webdot server:

    * Block everything

    * But allow "*.dot" only for the remote webdot server

  * Otherwise, if you use a local GraphViz:

    * Block everything

    * But allow: "*.png", "*.gif", "*.jpg", "*.map"

  * And if you don't use any dot:

    * Block everything

* In "Bugzilla": - Block everything

* In "template": - Block everything

Be sure to test that data that should not be accessed remotely is
properly blocked. Of particular interest is the localconfig file which
contains your database password. Also, be aware that many editors
create temporary and backup files in the working directory and that
those should also not be accessible. For more information, see bug
186383 or Bugtraq ID 6501. To test, simply run "testserver.pl", as
said above.

Note: Be sure to check *Web server* for instructions specific to the web
  server you use.


Bugzilla
========


Prevent users injecting malicious Javascript
--------------------------------------------

If you installed Bugzilla version 2.22 or later from scratch, then the
*utf8* parameter is switched on by default. This makes Bugzilla
explicitly set the character encoding, following a CERT advisory
recommending exactly this. The following therefore does not apply to
you; just keep *utf8* turned on.

If you've upgraded from an older version, then it may be possible for
a Bugzilla user to take advantage of character set encoding
ambiguities to inject HTML into Bugzilla comments. This could include
malicious scripts. This is because due to internationalization
concerns, we are unable to turn the *utf8* parameter on by default for
upgraded installations. Turning it on manually will prevent this
problem.
