(RHSA-2011:0885) Critical: 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 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-2011-2377)

Multiple dangling pointer flaws were found in Firefox. 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-2011-0083, CVE-2011-0085, CVE-2011-2363)

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-2011-2364, CVE-2011-2365, CVE-2011-2374, CVE-2011-2375,
CVE-2011-2376)

An integer overflow flaw was found in the way Firefox handled JavaScript
Array objects. A website containing malicious JavaScript could cause
Firefox to execute that JavaScript with the privileges of the user running
Firefox. (CVE-2011-2371)

A use-after-free flaw was 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-2011-2373)

It was found that Firefox could treat two separate cookies as
interchangeable if both were for the same domain name but one of those
domain names had a trailing “.” character. This violates the same-origin
policy and could possibly lead to data being leaked to the wrong domain.
(CVE-2011-2362)

For technical details regarding these flaws, refer to the Mozilla security
advisories for Firefox 3.6.18. You can find a link to the Mozilla
advisories in the References section of this erratum.

This update also fixes the following bug:

• With previous versions of Firefox on Red Hat Enterprise Linux 5, the
  “background-repeat” CSS (Cascading Style Sheets) property did not work
  (such images were not displayed and repeated as expected). (BZ#698313)

All Firefox users should upgrade to these updated packages, which contain
Firefox version 3.6.18, which corrects these issues. After installing the
update, Firefox must be restarted for the changes to take effect.