Mozilla Thunderbird is a standalone mail and newsgroup client.Several flaws were found in the processing of malformed HTML content.Malicious HTML content could cause Thunderbird to crash or, potentially,execute arbitrary code with the privileges of the user running Thunderbird.(CVE-2010-1585, CVE-2011-0053, CVE-2011-0062)A flaw was found in the way Thunderbird handled malformed JPEG images. AnHTML mail message containing a malicious JPEG image could causeThunderbird to crash or, potentially, execute arbitrary code with theprivileges of the user running Thunderbird. (CVE-2011-0061)All Thunderbird users should upgrade to this updated package, whichresolves these issues. All running instances of Thunderbird must berestarted for the update to take effect.