Google recently released version 45 in response to a security concern. This release also included 29 security fixes for the browser. For more specific information on these fixes, please see Chrome Releases – Stable Channel Update. Google (in addition to Mozilla and Microsoft) has announced that they would end support for the RC4 encryption algorithm by early 2016. Google has also implemented a default pause in Flash ads.
Note that Google Chrome Browsers do typically automatically update, but the update may require that you restart the browser. You can start the upgrade process in Chrome by simply going to About Chrome in the Help and about option in their menu.