SeaMonkey is an open source web browser, email and newsgroup client, IRC chat client, and HTML editor. Several flaws were found in the processing of malformed web content. A web page containing malicious content could cause SeaMonkey to crash or, potentially, execute arbitrary code with the privileges of the user running SeaMonkey. A buffer overflow flaw was found in SeaMonkey. A web page containing malicious content could cause SeaMonkey to crash or, potentially, execute arbitrary code with the privileges of the user running SeaMonkey. A use-after-free flaw and several dangling pointer flaws were found in SeaMonkey. A web page containing malicious content could cause SeaMonkey to crash or, potentially, execute arbitrary code with the privileges of the user running SeaMonkey. A cross-site scripting flaw was found in SeaMonkey. A web page containing malicious content could cause SeaMonkey to run JavaScript code with the permissions of a different website. All SeaMonkey users should upgrade to these updated packages, which correct these issues. After installing the update, SeaMonkey must be restarted for the changes to take effect.