An issue was discovered in certain Apple products. iOS before 10.2 is affected. macOS before 10.12.2 is affected. watchOS before 3.1.3 is affected. The issue involves the "Security" component, which makes it easier for attackers to bypass cryptographic protection mechanisms by leveraging use of the 3DES cipher.
https://support.apple.com/HT207487
https://support.apple.com/HT207423
https://support.apple.com/HT207422