After a long time since the last update Valve has been pushed the latest update in the form of Steam OS 2.115. The developers of this gaming Linux distro have called it is the biggest ever Steam update.
The Steam OS 2.115 is based on recently released Debian 8.8. Steam OS gets all latest security patches released.
Steam OS 2.115 implements AMD Vulkan support.
You can find complete Steam OS 2.115 change log here.