(RHSA-2009:1095) Critical: firefox security update

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

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 as the user running Firefox.
(CVE-2009-1392, CVE-2009-1832, CVE-2009-1833, CVE-2009-1837, CVE-2009-1838,
CVE-2009-1841)

Multiple flaws were found in the processing of malformed, local file
content. If a user loaded malicious, local content via the file:// URL, it
was possible for that content to access other local data. (CVE-2009-1835,
CVE-2009-1839)

A script, privilege elevation flaw was found in the way Firefox loaded XML
User Interface Language (XUL) scripts. Firefox and certain add-ons could
load malicious content when certain policy checks did not happen.
(CVE-2009-1840)

A flaw was found in the way Firefox displayed certain Unicode characters in
International Domain Names (IDN). If an IDN contained invalid characters,
they may have been displayed as spaces, making it appear to the user that
they were visiting a trusted site. (CVE-2009-1834)

A flaw was found in the way Firefox handled error responses returned from
proxy servers. If an attacker is able to conduct a man-in-the-middle attack
against a Firefox instance that is using a proxy server, they may be able
to steal sensitive information from the site the user is visiting.
(CVE-2009-1836)

For technical details regarding these flaws, refer to the Mozilla security
advisories for Firefox 3.0.11. You can find a link to the Mozilla
advisories in the References section of this errata.

All Firefox users should upgrade to these updated packages, which contain
Firefox version 3.0.11, which corrects these issues. After installing the
update, Firefox must be restarted for the changes to take effect.