[RHSA-2011:0310] firefox security and bug fix update

Mozilla Firefox is an open source web browser. XULRunner provides the XUL
Runtime environment for Mozilla Firefox.

A flaw was found in the way Firefox sanitized HTML content in extensions.
If an extension loaded or rendered malicious content using the
ParanoidFragmentSink class, it could fail to safely display the content,
causing Firefox to execute arbitrary JavaScript with the privileges of the
user running Firefox. (CVE-2010-1585)

A flaw was found in the way Firefox handled dialog boxes. An attacker could
use this flaw to create a malicious web page that would present a blank
dialog box that has non-functioning buttons. If a user closes the dialog
box window, it could unexpectedly grant the malicious web page elevated
privileges. (CVE-2011-0051)

Several flaws were found in the processing of malformed web content. A web
page containing malicious content could cause Firefox to crash or,
potentially, execute arbitrary code with the privileges of the user running
Firefox. (CVE-2011-0053, CVE-2011-0055, CVE-2011-0058, CVE-2011-0062)

Several flaws were found in the way Firefox handled malformed JavaScript. A
website containing malicious JavaScript could cause Firefox to execute that
JavaScript with the privileges of the user running Firefox. (CVE-2011-0054,
CVE-2011-0056, CVE-2011-0057)

A flaw was found in the way Firefox handled malformed JPEG images. A
website containing a malicious JPEG image could cause Firefox to crash or,
potentially, execute arbitrary code with the privileges of the user running
Firefox. (CVE-2011-0061)

A flaw was found in the way Firefox handled plug-ins that perform HTTP
requests. If a plug-in performed an HTTP request, and the server sent a 307
redirect response, the plug-in was not notified, and the HTTP request was
forwarded. The forwarded request could contain custom headers, which could
result in a Cross Site Request Forgery attack. (CVE-2011-0059)

For technical details regarding these flaws, refer to the Mozilla security
advisories for Firefox 3.6.14. You can find a link to the Mozilla
advisories in the References section of this erratum.

This update also fixes the following bug:

• On Red Hat Enterprise Linux 4 and 5, running the "firefox -setDefaultBrowser" command caused warnings such as the following:

libgnomevfs-WARNING **: Deprecated function. User modifications to the
MIME database are no longer supported.

This update disables the "setDefaultBrowser" option. Red Hat Enterprise
Linux 4 users wishing to set a default web browser can use Applications ->
Preferences -> More Preferences -> Preferred Applications. Red Hat
Enterprise Linux 5 users can use System -> Preferences -> Preferred
Applications. (BZ#463131, BZ#665031)

All Firefox users should upgrade to these updated packages, which contain
Firefox version 3.6.14, which corrects these issues. After installing the
update, Firefox must be restarted for the changes to take effect.