SeaMonkey is an open source web browser, email and newsgroup client, IRC chat client, and HTML editor. A cross-site scripting flaw was found in the way SeaMonkey handled certain multibyte character sets. 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 this issue. After installing the update, SeaMonkey must be restarted for the changes to take effect.