Magento have resolve several security issue and are asking all users with immediate effect to update their software below, and have released two security patches to be installed.

SUPEE-7405 (https://magento.com/security/patches/supee-7405 )

SUPEE-7616 (https://magento.com/blog/magento-news/usps-updates-coming-january-17 ),

For security purpose you should install both patches to your website as soon as possible, before updating to check that it's compatible with your website before updating software & make sure you have backup before updating, and fully test site again

Macintosh Electronics Ltd can update your site for you and it will require 9 hours engineers time, this can be prebooked if you like us do this  for you please call uk support help desk on +44 161 796 5272 or send email to our support team.