About Apple security updates
For our customers' protection, Apple doesn't disclose, discuss, or confirm security issues until an investigation has occurred and patches or releases are available. Recent releases are listed on the Apple security updates page.
Apple security documents reference vulnerabilities by CVE-ID when possible.
Pages 6.1, Numbers 4.1, and Keynote 7.1 for Mac and Pages 3.1, Numbers 3.1, and Keynote 3.1 for iOS
Released March 27, 2017
Available for: macOS 10.12 or later, iOS 10.0 or later
Impact: The contents of password-protected PDFs exported from iWork may be exposed
Description: iWork used weak 40-bit RC4 encryption for password-protected PDF exports. This issue was addressed by changing iWork export to use AES-128.
CVE-2017-2391: Philipp Eckel of ThoughtWorks