TastyIgniter through 4.4.5 contain a PHP object injection vulnerability that allows authenticated administrators to achieve arbitrary code execution by submitting a serialized PHP object as a settings value, which is stored unsanitized and later unserialized by getValueAttribute() when the setting is read. Attackers can submit a serialized gadget chain, such as one generated via phpggc, through the admin settings form (for example the maintenance_message setting loaded by CheckMaintenance.php) to achieve arbitrary operating-system command execution as the PHP application process user, with the impact persisting until the value is overwritten.