Apple has issued three Mac security updates:, and  for OS X 10.9.5 Mavericks and OS X 10.10.5 Yosemite. All three updates are related to the major vulnerabilities discovered in iOS by Citizen Lab and Lookout, as we reported in “ ” (25 August 2016). Due to the severity of these vulnerabilities, we encourage everyone to install these updates as soon as possible.
You can download the 414.9 MB and the 468 MB  directly from Apple’s Web site, though it’s easier to install them via Software Update. Safari 9.1.3 is available only via Software Update.