Security Update 2017-003 (Yosemite and El Capitan)

Apple has released Security Update 2017-003 for OS X 10.10 Yosemite and 10.11 El Capitan, patching security vulnerabilities that the company also addressed in macOS 10.12.6 Sierra (see “Apple Releases macOS 10.12.6, iOS 10.3.3, watchOS 3.2.3, and tvOS 10.2.2,” 19 July 2017). The security update addresses a variety of memory corruption issues that affected kernel and system privileges and could lead to arbitrary code execution. It also improves bounds checking to prevent a maliciously crafted XML document from disclosing user information. However, it does not address the BroadPwn bug (see “iOS 10.3.3 Patches High-Profile BroadPwn Flaw,”
21 July 2017). Apple recommends it for all users. (Free. For 10.10.5 Yosemite, 431.6 MB; for 10.11.6 El Capitan, 763.9 MB; security content release notes)