As you may know, Canonical is releasing security updates for all the supported Ubuntu systems very often, in order to help the users stay safe.
Recently, two Swift vulnerabilities have been found and patched in Ubuntu 15.04, Ubuntu 14.04 and Ubuntu 12.04. Obviously, the security fixes are available for the derivative systems as well, the systems sharing the same repos.
So, in order to stay safe, just perform a system upgrade on your Ubuntu 15.04 Vivid Vervet, Ubuntu 14.04 Trusty Tahr, Ubuntu 12.04 Precise Pangolin or a derivative system like Linux Mint 17.2 Rafaela, Linux Mint 17.1 Rebecca, Linux Mint 17 Qiana, Linux Mint 13 Maya, Pinguy OS 14.04, Elementary OS 0.3 Freya, Deepin 2014, Peppermint 6, Peppermint 5, LXLE 14.04 and Linux Lite 2. Like this:
$ sudo apt-get update
$ sudo apt-get dist-upgrade