This is a security release for the 3.x series and it only contains the security fixes, no other changes have been made. It is strongly suggested that you update your Joomla! website to the latest version.
You can find more info about these issue at the Joomla! release news.
We have released Bitnami Joomla! 3.4.5 installers, virtual machines and Amazon EC2, Google, VMware vCloud Air, DigitalOcean and Azure cloud images that fix these issues.
Do you already have a Joomla! installation? You can follow our guide about how to upgrade the application and you won't have to be worried about these vulnerabilities.
Have questions about Bitnami Joomla! or the security issue? Post to our community forum, and we would be happy to help you.