SquirrelMail is a standards-based webmail package written in PHP. Form submissions in SquirrelMail did not implement protection against Cross-Site Request Forgery attacks. If a remote attacker tricked a user into visiting a malicious web page, the attacker could hijack that user"s authentication, inject malicious content into that user"s preferences, or possibly send mail without that user"s permission. Users of SquirrelMail should upgrade to this updated package, which contains a backported patch to correct these issues.