Mozilla Thunderbird is a standalone mail and newsgroup client. Several flaws were found in the processing of malformed web content. A web page containing malicious content could cause Thunderbird to crash or, potentially, execute arbitrary code with the privileges of the user running Thunderbird. Red Hat would like to thank the Mozilla project for reporting these issues. Upstream acknowledges Gary Kwong, Christoph Diehl, Christian Holler, Hannes Verschore, Jan de Mooij, Ryan VanderMeulen, Jeff Walden, Kyle Huey, Abhishek Arya, and Nils as the original reporters of these issues. Note: All of the above issues 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. For technical details regarding these flaws, refer to the Mozilla security advisories for Thunderbird 24.6.0. You can find a link to the Mozilla advisories in the References section of this erratum. All Thunderbird users should upgrade to this updated package, which contains Thunderbird version 24.6.0, which corrects these issues. After installing the update, Thunderbird must be restarted for the changes to take effect.