(RHSA-2012:0085) Critical: thunderbird security update

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.