An issue was discovered in certain Apple products. iOS before 10.2.1 is affected. watchOS before 3.1.3 is affected. The issue involves the "Unlock with iPhone" component, which allows attackers to bypass the wrist-presence protection mechanism and unlock a Watch device via unspecified vectors.
Apple Security Advisory 2017-01-23-1 - iOS 10.2.1 is now available and addresses logic issues, code execution, and multiple other security vulnerabilities.