About the security content of iOS 11.2.1

This document describes the security content of iOS 11.2.1.

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iOS 11.2.1

Released December 13, 2017

HomeKit

Available for: iPhone 5s and later, iPad Air and later, and iPod touch 6th generation

Impact: A remote attacker may be able to unexpectedly alter application state

Description: A message handling issue was addressed with improved input validation.

CVE-2017-13903: Tian Zhang

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Published Date: December 13, 2017