Critical: thunderbird security update

An updated thunderbird package that fixes two security issues is now
available for Red Hat Enterprise Linux 4 and 5.

The Red Hat Security Response Team has rated this update as having critical
security impact. Common Vulnerability Scoring System (CVSS) base scores,
which give detailed severity ratings, are available for each vulnerability
from the CVE links in the References section.

Mozilla Thunderbird is a standalone mail and newsgroup client.

A flaw was found in the processing of malformed content. An HTML mail
message containing malicious content could cause Thunderbird to crash or,
potentially, execute arbitrary code with the privileges of the user running
Thunderbird. (CVE-2012-0442)

The same-origin policy in Thunderbird treated http://example.com and
http://[example.com] as interchangeable. A malicious script could possibly
use this flaw to gain access to sensitive information (such as a client's
IP and user e-mail address, or httpOnly cookies) that may be included in
HTTP proxy error replies, generated in response to invalid URLs using
square brackets. (CVE-2011-3670)

Note: The CVE-2011-3670 issue cannot be exploited by a specially-crafted
HTML mail message as JavaScript is disabled by default for mail messages.
It could be exploited another way in Thunderbird, for example, when viewing
the full remote content of an RSS feed.

All Thunderbird users should upgrade to this updated package, which
resolves these issues. All running instances of Thunderbird must be
restarted for the update to take effect.

Before applying this update, make sure all previously-released errata
relevant to your system have been applied.

This update is available via the Red Hat Network. Details on how to
use the Red Hat Network to apply this update are available at
https://access.redhat.com/kb/docs/DOC-11259

785085 - CVE-2012-0442 Mozilla: memory safety hazards in 10.0/1.9.2.26 (MFSA 2012-01)
785464 - CVE-2011-3670 Mozilla: Same-origin bypass using IPv6-like hostname syntax (MFSA 2012-02)

https://www.redhat.com/security/data/cve/CVE-2011-3670.html
https://www.redhat.com/security/data/cve/CVE-2012-0442.html
https://access.redhat.com/security/updates/classification/#critical