Mozilla Thunderbird is a standalone mail and newsgroup client. Several flaws were found in the processing of malformed content. Malicious content could cause Thunderbird to crash or, potentially, execute arbitrary code with the privileges of the user running Thunderbird. A flaw was found in the way Chrome Object Wrappers were implemented. Malicious content could be used to cause Thunderbird to execute arbitrary code via plug-ins installed in Thunderbird. A flaw in the way Thunderbird displayed URL values could allow malicious content or a user to perform a phishing attack. An information disclosure flaw was found in the way certain JavaScript functions were implemented in Thunderbird. An attacker could use this flaw to bypass Address Space Layout Randomization and other security restrictions. Red Hat would like to thank the Mozilla project for reporting these issues. Upstream acknowledges Atte Kettunen, Boris Zbarsky, pa_kt, regenrecht, Abhishek Arya, Christoph Diehl, Christian Holler, Mats Palmgren, Chiaki Ishikawa, Mariusz Mlynski, Masato Kinugawa, and Jesse Ruderman as the original reporters of these issues. Note: All issues except CVE-2013-0744, CVE-2013-0753, and CVE-2013-0754 cannot be exploited by a specially-crafted HTML mail message as JavaScript is disabled by default for mail messages. They 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 contains Thunderbird version 10.0.12 ESR, which corrects these issues. After installing the update, Thunderbird must be restarted for the changes to take effect.