Smarty is a template engine for PHP. The "template security" feature of Smarty is designed to help reduce the risk of a system compromise when you have untrusted parties editing templates.
A vulnerability has been discovered within the regex_replace modifier of the Smarty templates when allowing access to untrusted users. Furthermore, it was possible to call functions from {if} statements and {math} functions.
These issues may allow a remote attacker to bypass the "template security" feature of Smarty, and execute arbitrary PHP code.
Do not grant template access to untrusted users.
All Smarty users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=dev-php/smarty-2.6.9"